/***********Template Starts Here***********/
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <map>
#include <queue>
#include <stack>
#include <vector>
#include <deque>
#include <functional>
#include <string>
#include <iostream>
#include <cctype>
#include <set>
#include <climits>
#include <iomanip>
#include <cassert>
//#include <unordered_map>
#define pb push_back
#define nl puts ("")
#define sp printf ( " " )
#define phl printf ( "hello\n" )
#define ff first
#define ss second
#define POPCOUNT __builtin_popcountll
#define RIGHTMOST __builtin_ctzll
#define LEFTMOST(x) (63-__builtin_clzll((x)))
#define MP make_pair
#define FOR(i,x,y) for(int i = (x) ; i <= (y) ; ++i)
#define ROF(i,x,y) for(int i = (y) ; i >= (x) ; --i)
#define CLR(x,y) memset(x,y,sizeof(x))
#define UNIQUE(V) (V).erase(unique((V).begin(),(V).end()),(V).end())
#define MIN(a,b) ((a)<(b)?(a):(b))
#define MAX(a,b) ((a)>(b)?(a):(b))
#define NUMDIGIT(x,y) (((int)(log10((x))/log10((y))))+1)
#define SQ(x) ((x)*(x))
#define ABS(x) ((x)<0?-(x):(x))
#define FABS(x) ((x)+eps<0?-(x):(x))
#define ALL(x) (x).begin(),(x).end()
#define LCM(x,y) (((x)/gcd((x),(y)))*(y))
#define SZ(x) ((int)(x).size())
#define NORM(x) if(x>=mod)x-=mod;
using namespace std;
typedef long long vlong;
typedef unsigned long long uvlong;
typedef pair < int, int > pii;
typedef pair < vlong, vlong > pll;
typedef vector<pii> vii;
typedef vector<int> vi;
const vlong inf = 2147383647;
const double pi = 2 * acos ( 0.0 );
const double eps = 1e-9;
#ifdef forthright48
#include <ctime>
clock_t tStart = clock();
#define debug(args...) {dbg,args; cerr<<endl;}
#define timeStamp printf("Execution Time: %.2fs\n", (double)(clock() - tStart)/CLOCKS_PER_SEC)
#else
#define debug(args...) // Just strip off all debug tokens
#define timeStamp
#endif
struct debugger{
template<typename T> debugger& operator , (const T& v){
cerr<<v<<" ";
return *this;
}
}dbg;
//int knightDir[8][2] = { {-2,1},{-1,2},{1,2},{2,1},{2,-1},{-1,-2},{1,-2},{-2,-1} };
//int dir4[4][2] = {{-1,0},{0,1},{1,0},{0,-1}};
inline vlong gcd ( vlong a, vlong b ) {
a = ABS ( a ); b = ABS ( b );
while ( b ) { a = a % b; swap ( a, b ); } return a;
}
vlong ext_gcd ( vlong A, vlong B, vlong *X, vlong *Y ){
vlong x2, y2, x1, y1, x, y, r2, r1, q, r;
x2 = 1; y2 = 0;
x1 = 0; y1 = 1;
for (r2 = A, r1 = B; r1 != 0; r2 = r1, r1 = r, x2 = x1, y2 = y1, x1 = x, y1 = y ) {
q = r2 / r1;
r = r2 % r1;
x = x2 - (q * x1);
y = y2 - (q * y1);
}
*X = x2; *Y = y2;
return r2;
}
inline vlong modInv ( vlong a, vlong m ) {
vlong x, y;
ext_gcd( a, m, &x, &y );
if ( x < 0 ) x += m; //modInv is never negative
return x;
}
inline vlong power ( vlong a, vlong p ) {
vlong res = 1, x = a;
while ( p ) {
if ( p & 1 ) res = ( res * x );
x = ( x * x ); p >>= 1;
}
return res;
}
inline vlong bigmod ( vlong a, vlong p, vlong m ) {
vlong res = 1 % m, x = a % m;
while ( p ) {
if ( p & 1 ) res = ( res * x ) % m;
x = ( x * x ) % m; p >>= 1;
}
return res;
}
/***********Template Ends Here***********/
/*********** Hasib Templates Starts Here**********/
#include<bits/stdc++.h>
using namespace std;
#define loop(i, n) for(int i=0; i<(n); i++)
#define sf scanf
#define pf printf
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) (v).begin(), (v).end()
#define PI acos(-1.0)
#define mem(ara, val) memset(ara, val, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define vdump(x) cerr<<#x<<" = "<<x<<endl;
#define dump(args...) cerr,args; cerr<<endl
template<typename T>
ostream& operator<<(ostream& out, vector<T> v)
{
out<<"[ ";
loop(i, SZ(v))
{
if(i) out<<", ";
out<<v[i];
}
out<<" ]";
return out;
}
template<typename T1, typename T2>
ostream& operator<<(ostream &out, pair<T1, T2> p)
{
out<<"( "<<p.fr<<", "<<p.sc<<")";
return out;
}
template<typename T>
ostream& operator,(ostream &out, T x)
{
out<<x<<" ";
return out;
}
/**********Hasib Templates Ends Here**************/
/**
* WARTNING for me:
* Never use FOR
* Never use pii, pll, vi, vi
* Never use ff, ss, phl, sp, nl
*/
#define NODE 5100
#define MAXX 107
struct KUHN{
int left[NODE], right[NODE], vis[NODE], cc;
vector<int> adj[NODE];
KUHN() : cc(1) {
}
void clear(int n)
{
FOR(i, 0, n) adj[i].clear();
}
bool tryK(int v)
{
if(vis[v] == cc) return false;
vis[v] = cc;
loop(i, SZ(adj[v]))
{
int t = adj[v][i];
if(right[t] == -1)
{
right[t] = v; left[v] = t;
return true;
}
}
loop(i, SZ(adj[v]))
{
int t = adj[v][i];
if( tryK(right[t]))
{
right[t] = v; left[v] = t;
return true;
}
}
return false;
}
int match(int n)
{
int res = 0;
bool done;
CLR(left, -1); CLR(right, -1);
do{
done = true; cc++;
FOR(i, 0, n)
{
if(left[i] == -1 && tryK(i))
{
done = false;
}
}
}while(!done);
FOR(i, 0, n) res += (left[i] != -1);
return res;
}
}kuhn;
char grid[MAXX][MAXX];
int N, M;
#define index sflajfsa
paii index[MAXX][MAXX];
void solve()
{
int r = 0, c = 0;
loop(i, N)
{
loop(j, M)
{
if(j == 0)
{
r++;
if(grid[i][j] == '.')
{
index[i][j].fr = r;
}
}
else
{
if(grid[i][j] == '.')
{
index[i][j].fr = r;
}
else
{
index[i][j].fr = -1;
if(grid[i][j] == 'W' && grid[i][j-1] != 'W' )
{
r++;
}
}
}
}
}
loop(j, M)
{
loop(i, N)
{
if(i == 0)
{
c++;
if(grid[i][j] == '.')
{
index[i][j].sc = c;
}
}
else
{
if(grid[i][j] == '.')
{
index[i][j].sc = c;
}
else
{
index[i][j].sc = -1;
if(grid[i-1][j] != 'W' && grid[i][j] == 'W')
{
c++;
}
}
}
}
}
kuhn.clear(r+2);
loop(i, N)
{
loop(j, M)
{
if(grid[i][j] == '.')
{
kuhn.adj[ index[i][j].fr ].pb( index[i][j].sc );
}
}
}
int m = kuhn.match(r + 2);
pf("%d\n", m);
int u, v;
loop(i, N)
{
loop(j, M)
{
if(grid[i][j] == '.')
{
u = index[i][j].fr;
v = index[i][j].sc;
if(kuhn.left[u] == v)
{
pf("T");
}
else
{
pf(".");
}
}
else
{
pf("%c", grid[i][j]);
}
}
pf("\n");
}
}
int main()
{
#ifdef hasibpc
read("input.txt");
//write("output.txt");
#endif
int kases, kaseno = 0;
sf("%d", &kases);
while(kases--)
{
sf("%d %d", &N, &M);
loop(i, N)
{
sf("%s", grid[i]);
}
pf("Case %d: ", ++kaseno);
solve();
}
}
Category Archives: Graph
(LightOJ) 1218 – Multiple Free Subset
0Step 1. Sort the array.
Step 2. Remove duplicates.
Step 3. Make a bipartite graph. There should be a connection from i to j iff i divides j.
Step 4. Start from the smallest number, and follow the next steps repeatedly.
– Remove all the multiples of this number from the graph. Remove from both sides of bipartite graph.
– Now check, if we can create exactly same size of maximum independent set as before.
– If possible, parmanently delete those multiples and push the current number into result array. If not possible, restore the previous graph.
/***********Template Starts Here***********/
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include
<map>
#include <queue>
#include <stack>
#include <vector>
#include <deque>
#include <functional>
#include <string>
#include <iostream>
#include <cctype>
#include <set>
#include <climits>
#include <iomanip>
#include <cassert>
//#include <unordered_map>
#define pb push_back
#define nl puts ("")
#define sp printf ( " " )
#define phl printf ( "hello\n" )
#define ff first
#define ss second
#define POPCOUNT __builtin_popcountll
#define RIGHTMOST __builtin_ctzll
#define LEFTMOST(x) (63-__builtin_clzll((x)))
#define MP make_pair
#define FOR(i,x,y) for(int i = (x) ; i <= (y) ; ++i) #define ROF(i,x,y) for(int i = (y) ; i >= (x) ; --i)
#define CLR(x,y) memset(x,y,sizeof(x))
#define UNIQUE(V) (V).erase(unique((V).begin(),(V).end()),(V).end())
#define MIN(a,b) ((a)<(b)?(a):(b)) #define MAX(a,b) ((a)>(b)?(a):(b))
#define NUMDIGIT(x,y) (((int)(log10((x))/log10((y))))+1)
#define SQ(x) ((x)*(x))
#define ABS(x) ((x)<0?-(x):(x))
#define FABS(x) ((x)+eps<0?-(x):(x)) #define ALL(x) (x).begin(),(x).end() #define LCM(x,y) (((x)/gcd((x),(y)))*(y)) #define SZ(x) ((int)(x).size()) #define NORM(x) if(x>=mod)x-=mod;
using namespace std;
typedef long long vlong;
typedef unsigned long long uvlong;
typedef pair < int, int > pii;
typedef pair < vlong, vlong > pll;
typedef vector<pii> vii;
typedef vector<int> vi;
const vlong inf = 2147383647;
const double pi = 2 * acos ( 0.0 );
const double eps = 1e-9;
#ifdef forthright48
#include <ctime>
clock_t tStart = clock();
#define debug(args...) {dbg,args; cerr<<endl;}
#define timeStamp printf("Execution Time: %.2fs\n", (double)(clock() - tStart)/CLOCKS_PER_SEC)
#else
#define debug(args...) // Just strip off all debug tokens
#define timeStamp
#endif
struct debugger{
template<typename T> debugger& operator , (const T& v){
cerr<<v<<" ";
return *this;
}
}dbg;
//int knightDir[8][2] = { {-2,1},{-1,2},{1,2},{2,1},{2,-1},{-1,-2},{1,-2},{-2,-1} };
//int dir4[4][2] = {{-1,0},{0,1},{1,0},{0,-1}};
inline vlong gcd ( vlong a, vlong b ) {
a = ABS ( a ); b = ABS ( b );
while ( b ) { a = a % b; swap ( a, b ); } return a;
}
vlong ext_gcd ( vlong A, vlong B, vlong *X, vlong *Y ){
vlong x2, y2, x1, y1, x, y, r2, r1, q, r;
x2 = 1; y2 = 0;
x1 = 0; y1 = 1;
for (r2 = A, r1 = B; r1 != 0; r2 = r1, r1 = r, x2 = x1, y2 = y1, x1 = x, y1 = y ) {
q = r2 / r1;
r = r2 % r1;
x = x2 - (q * x1);
y = y2 - (q * y1);
}
*X = x2; *Y = y2;
return r2;
}
inline vlong modInv ( vlong a, vlong m ) {
vlong x, y;
ext_gcd( a, m, &x, &y );
if ( x < 0 ) x += m; //modInv is never negative return x; } inline vlong power ( vlong a, vlong p ) { vlong res = 1, x = a; while ( p ) { if ( p & 1 ) res = ( res * x ); x = ( x * x ); p >>= 1;
}
return res;
}
inline vlong bigmod ( vlong a, vlong p, vlong m ) {
vlong res = 1 % m, x = a % m;
while ( p ) {
if ( p & 1 ) res = ( res * x ) % m;
x = ( x * x ) % m; p >>= 1;
}
return res;
}
/***********Template Ends Here***********/
/*********** Hasib Templates Starts Here**********/
#include<bits/stdc++.h>
using namespace std;
#define loop(i, n) for(int i=0; i<(n); i++)
#define sf scanf
#define pf printf
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) (v).begin(), (v).end()
#define PI acos(-1.0)
#define mem(ara, val) memset(ara, val, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define vdump(x) cerr<<#x<<" = "<<x<<endl;
#define dump(args...) cerr,args; cerr<<endl
template<typename T>
ostream& operator<<(ostream& out, vector<T> v)
{
out<<"[ ";
loop(i, SZ(v))
{
if(i) out<<", ";
out<<v[i];
}
out<<" ]";
return out;
}
template<typename T1, typename T2>
ostream& operator<<(ostream &out, pair<T1, T2> p)
{
out<<"( "<<p.fr<<", "<<p.sc<<")";
return out;
}
template<typename T>
ostream& operator,(ostream &out, T x)
{
out<<x<<" ";
return out;
}
/**********Hasib Templates Ends Here**************/
/**
* WARTNING for me:
* Never use FOR
* Never use pii, pll, vi, vi
* Never use ff, ss, phl, sp, nl
*/
int N;
vector<int>v;
#define NODE 107
int mark[NODE];
struct KUHN{
int left[NODE], right[NODE], vis[NODE], cc;
vector<int>adj[NODE];
KUHN() : cc(1) {}
void clear(int n)
{
FOR(i, 0, n) adj[i].clear();
}
bool tryK(int v)
{
if (vis[v] == cc) return false;
vis[v] = cc;
loop(i, SZ(adj[v]))
{
int t = adj[v][i];
if(mark[t]) continue;
if(right[t] == -1)
{
right[t] = v; left[v] = t;
return true;
}
}
loop(i, SZ(adj[v]))
{
int t = adj[v][i];
if(mark[t]) continue;
if(tryK(right[t]))
{
right[t] = v; left[v] = t;
return true;
}
}
return false;
}
int match(int n)
{
int res = 0;
bool done;
CLR(left, -1); CLR(right, -1);
do{
done = true;
cc++;
FOR(i, 0, n)
{
if(mark[i]) continue;
if(left[i] == -1 && tryK(i))
{
done = false;
}
}
}while(!done);
FOR(i, 0, n)
{
if(mark[i]) continue;
res += (left[i] != -1);
}
return res;
}
}kuhn;
void solve()
{
sort(all(v));
UNIQUE(v);
N = SZ(v);
kuhn.clear(N + 2);
loop(i, N)
{
for(int j=i+1; j<N; j++)
{
if( (v[j] % v[i]) == 0 )
{
//vdump(MP(i,j));
kuhn.adj[i].pb(j);
}
}
}
mem(mark, 0);
int M = N - kuhn.match(N+2);
vector<int>result;
int m;
int prevMarked = 0;
loop(i, N)
{
if(mark[i]) continue;
m = 0;
for(int j=i+1; j<N; j++)
{
if( (mark[j] == 0) && (v[j] % v[i] == 0) )
{
mark[j] = 2;
m++;
}
}
int tmp = (N - m - prevMarked - kuhn.match(N+2));
if(tmp == M )
{
result.pb(i);
prevMarked += m;
m = 1;
}
else
{
m = 0;
}
loop(i, N)
{
if(mark[i] == 2)
{
mark[i] = m;
}
}
}
loop(i, M)
{
pf(" %d", v[result[i]]);
}
pf("\n");
}
int main ()
{
#ifdef hasibpc
read("input.txt");
//write("output.txt");
#endif // hasibpc
int kases, kaseno = 0;
sf("%d", &kases);
while(kases--)
{
sf("%d", &N);
v.resize(N);
loop(i, N)
{
sf("%d", &v[i]);
}
pf("Case %d:", ++kaseno);
solve();
}
return 0;
}
(LightOj) 1291 – Real Life Traffic
0
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 10007
vector<int>graph[MAXX];
int n, m;
map<int, map<int, int> > isBridge;
bool visited[MAXX];
int low[MAXX], disc[MAXX];
int parent[MAXX];
int t;
vector<paii>bridges;
int cnt[MAXX];
void dfs_bridge(int u)
{
visited[u] = true;
low[u] = disc[u] = ++t;
loop(i, SZ(graph[u]))
{
int v = graph[u][i];
if( ! visited[v])
{
parent[v] = u;
dfs_bridge(v);
low[u] = min(low[u], low[v]);
if(low[v] > disc[u] )
{
bridges.pb(MP(u, v));
isBridge[u][v] = isBridge[v][u] = 1;
}
}
else if( v != parent[u])
{
low[u] = min(low[u], disc[v]);
}
}
}
int find(int u)
{
if(u == parent[u]) return u;
else return parent[u] = find(parent[u]);
}
int main()
{
int kases, kaseno = 0;
take(kases);
while(kases--)
{
loop(i, MAXX) graph[i].clear();
isBridge.clear();
take(n, m);
int u, v;
loop(i, m)
{
take(u, v);
graph[u].pb(v);
graph[v].pb(u);
}
mem(visited, 0);
mem(parent, -1);
t = 0;
bridges.clear();
loop(i, n)
{
if(!visited[i])
{
dfs_bridge(i);
}
}
loop(i, n)
{
parent[i] = i;
}
loop(i, n)
{
loop(j, SZ(graph[i]))
{
int v = graph[i][j];
if(isBridge[i][v] != 1)
{
//cerr<<"i is "<<i<<" and v = "<<v<<" "<<isBridge[u][v]<<endl;
int u = find(i);
v = find(v);
if( u != v)
{
parent[u] = v;
//cerr<<"connecting "<<u<<" and "<<v<<endl;
}
}
else
{
//dump(u); dump(v);
//cerr<<"here"<<endl;
}
}
}
mem(cnt, 0);
loop(i, SZ(bridges))
{
int u = bridges[i].fr, v = bridges[i].sc;
u = find(u);
v = find(v);
//dump(u); dump(v);
cnt[u]++;
cnt[v]++;
}
int ret = 0;
loop(i, n)
{
if(cnt[i] == 1)
{
ret++;
}
}
//ret = count of leaf
ret = (ret + 1)/2;
pf("Case %d: %d\n", ++kaseno, ret);
}
}
(LightOj) 1063 – Ant Hills
0
// link: http://lightoj.com/volume_showproblem.php?problem=1063
// tuto: http://www.geeksforgeeks.org/articulation-points-or-cut-vertices-in-a-graph/
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 10007
int N, M;
vector<int>adj[MAXX];
bool visited[MAXX];
int parent[MAXX];
int low[MAXX];
int disc[MAXX];
int tyme;
bool isArticulationPoint[MAXX];
void init()
{
loop(i, MAXX)
{
adj[i].clear();
visited[i] = false;
parent[i] = -1;
isArticulationPoint[i] = false;
}
tyme = 0;
}
void dfs_articulation_point(int u)
{
visited[u] = true;
disc[u] = low[u] = ++tyme;
int cntChild = 0;
loop(i, SZ(adj[u]))
{
int v = adj[u][i];
if( ! visited[v] )
{
cntChild++;
parent[v] = u;
dfs_articulation_point(v);
low[u] = min(low[u], low[v]);
if(parent[u] != -1)
{
if(low[v] >= disc[u])
{
isArticulationPoint[u] = true;
}
}
}
else if(v != parent[u])
{
low[u] = min(low[u], disc[v]);
}
}
if(parent[u] == -1)
{
if(cntChild > 1)
{
isArticulationPoint[u] = true;
}
}
}
int main()
{
int kases, kaseno = 0;
take(kases);
while(kases--)
{
take(N, M);
init();
int u, v;
loop(i, M)
{
take(u, v);
adj[u].pb(v);
adj[v].pb(u);
}
for(int i=1; i<=N; i++)
{
if( ! visited[i] )
{
dfs_articulation_point(i);
}
}
int cntArticulationPoint = 0;
for(int i=1; i<=N; i++)
{
if(isArticulationPoint[i]) cntArticulationPoint++;
}
pf("Case %d: %d\n",++kaseno, cntArticulationPoint);
}
}
(LighOj) 1026 – Critical Links
0
//link: http://lightoj.com/volume_showproblem.php?problem=1026
//tuto: http://www.geeksforgeeks.org/bridge-in-a-graph/
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 10007
int n;
vector<int>adj[MAXX];
int tyme;
bool visited[MAXX];
int parent[MAXX];
int low[MAXX];
int disc[MAXX];
vector<paii>bridges;
void dfs_bridge(int u)
{
visited[u] = true;
disc[u] = low[u] = ++tyme;
int child = 0;
loop(i, SZ(adj[u]))
{
int v = adj[u][i];
if( ! visited[v])
{
parent[v] = u;
dfs_bridge(v);
low[u] = min(low[u], low[v]);
if( low[v] > disc[u] )
{
bridges.pb(min(MP(u, v), MP(v, u)));
}
}
else if( v != parent[u] )
{
low[u] = min(low[u], disc[v]);
}
}
}
int main()
{
int kases, kaseno = 0;
sf("%d", &kases);
while(kases--)
{
sf("%d", &n);
int u, k, v;
char ch;
loop(i, n)
{
adj[i].clear();
parent[i] = -1;
visited[i] = false;
}
bridges.clear();
loop(i, n)
{
sf("%d %c%d%c", &u, &ch, &k, &ch);
loop(j, k)
{
sf("%d", &v);
adj[u].pb(v);
}
}
loop(i, n)
{
if( ! visited[i] )
{
dfs_bridge(i);
}
}
pf("Case %d:\n", ++kaseno);
pf("%d critical links\n", SZ(bridges));
sort(all(bridges));
loop(i, SZ(bridges))
{
pf("%d - %d\n", bridges[i].fr, bridges[i].sc);
}
}
}
(LightOj) 1141 – Number Transformation
0
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 1007
vector<int>factors[MAXX];
vector<int>primes;
void generatePrimes()
{
bool isPrime[MAXX];
mem(isPrime, 1);
int root = sqrt(MAXX) + 7;
for(int i=3; i<root; i++)
{
if(isPrime[i])
{
for(int j=i*i; j<MAXX; j+=(2*i))
{
isPrime[j] = false;
}
}
}
for(int i=2; i<MAXX;)
{
if(isPrime[i])
{
for(int j=2; i*j < MAXX; j++)
{
factors[i*j].pb(i);
}
}
if(i == 2)
{
i++;
}
else
{
i += 2;
}
}
}
void init()
{
generatePrimes();
}
int bfs(int source, int target)
{
bool visited[MAXX];
int dist[MAXX];
mem(dist, -1);
mem(visited, 0);
queue<int>Q;
Q.push(source);
visited = true;
dist = 0;
while(!Q.empty())
{
int u = Q.front(); Q.pop();
loop(i, SZ(factors[u]))
{
int v = u + factors[u][i];
if( (v <= target) && !visited[v] )
{
visited[v] = true;
dist[v] = dist[u] + 1;
if(v == target)
{
break;
}
Q.push(v);
}
}
}
return dist[target];
}
int main()
{
init();
int kases, kaseno = 0;
int s, t;
sf("%d", &kases);
while(kases--)
{
sf("%d %d", &s, &t);
pf("Case %d: %d\n", ++kaseno, bfs(s, t));
}
return 0;
}
(LightOj) 1154 – Penguins
0
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 208
#define INF (1<<29)
int capacity[MAXX][MAXX], tmpCapacity[MAXX][MAXX];
int N;
double D;
pair<double, double>points[MAXX/2];
vector<int>graph[MAXX];
int source, sink;
int total;
double sq(double x)
{
return x*x;
}
double dist(pair<double, double>A, pair<double, double>B)
{
return sqrt( sq(A.fr - B.fr) + sq(A.sc - B.sc) );
}
int findPath()
{
bool visited[MAXX];
bool found = false;
int parent[MAXX];
mem(parent, -1);
mem(visited, 0);
queue<int>Q;
Q.push(source);
visited = true;
while(!Q.empty())
{
int u = Q.front(); Q.pop();
loop(i, SZ(graph[u]))
{
int v = graph[u][i];
if(!visited[v] && tmpCapacity[u][v] > 0)
{
visited[v] = true;
parent[v] = u;
Q.push(v);
if(v == sink)
{
found = true;
break;
}
}
}
if(found)
{
break;
}
}
int pathCapacity = INF;
int u, v = sink;
while(parent[v] != -1)
{
u = parent[v];
pathCapacity = min(pathCapacity, tmpCapacity[u][v]);
v = u;
}
v = sink;
while(parent[v] != -1)
{
u = parent[v];
tmpCapacity[u][v] -= pathCapacity;
tmpCapacity[v][u] += pathCapacity;
v = u;
}
return found?pathCapacity:0;
}
int FLOW()
{
loop(i, MAXX)
{
loop(j, MAXX)
{
tmpCapacity[i][j] = capacity[i][j];
}
}
int ret = 0;
int pathCapacity;
while(pathCapacity = findPath())
{
ret += pathCapacity;
}
return ret;
}
void init()
{
}
int main()
{
init();
int kases, kaseno = 0;
int n, c;
int u, v;
sf("%d", &kases);
while(kases--)
{
mem(capacity, 0);
loop(i, MAXX) graph[i].clear();
total = 0;
sf("%d %lf", &N, &D);
source = 0;
for(int i=1; i<=N; i++)
{
sf("%lf %lf %d %d", &points[i].fr, &points[i].sc, &n, &c);
total += n;
v = 2*i;
u = v - 1;
graph[u].pb(v);
graph[v].pb(u);
capacity[u][v] = c;
graph.pb(u);
graph[u].pb(source);
capacity[u] = n;
}
for(int i=1; i<=N; i++)
{
for(int j=1; j<=N; j++)
{
if(i == j) continue;
if(dist(points[i], points[j]) <= D)
{
u = 2*i;
v = 2*j - 1;
capacity[u][v] = INF;
graph[u].pb(v);
graph[v].pb(u);
}
}
}
vector<int>vv;
for(int i=1; i<=N; i++)
{
sink = 2*i - 1;
if(FLOW() == total)
{
vv.pb(i);
}
}
printf("Case %d:", ++kaseno);
if(SZ(vv) == 0)
{
printf(" -1");
}
else
{
loop(i, SZ(vv))
{
printf(" %d", vv[i] - 1);
}
}
pf("\n");
}
return 0;
}
(LightOj) 1155 – Power Transmission
0
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
#define MAXX 207
#define INF (1<<29)
int source, sink;
int N;
int M;
int capacity[MAXX][MAXX];
vector<int>graph[MAXX];
int findPath()
{
bool visited[MAXX];
int parent[MAXX];
mem(parent, -1);
mem(visited, 0);
queue<int>Q;
Q.push(source);
visited = true;
bool found = false;
while(!Q.empty())
{
int u = Q.front(); Q.pop();
loop(i, SZ(graph[u]))
{
int v = graph[u][i];
if(!visited[v] && capacity[u][v] > 0)
{
visited[v] = true;
Q.push(v);
parent[v] = u;
if(v == sink)
{
found = true;
break;
}
}
}
if(found)
{
break;
}
}
int v = sink;
int pathCapacity = INF;
while(parent[v] != -1)
{
int u = parent[v];
pathCapacity = min(pathCapacity, capacity[u][v] );
v = u;
}
v = sink;
while(parent[v] != -1)
{
int u = parent[v];
capacity[u][v] -= pathCapacity;
capacity[v][u] += pathCapacity;
v = u;
}
if(found)
{
return pathCapacity;
}
else
{
return 0;
}
}
int FLOW()
{
int result = 0;
int pathCapacity;
while(true)
{
pathCapacity = findPath();
if(pathCapacity == 0)
{
break;
}
else
{
result += pathCapacity;
}
}
return result;
}
int solve()
{
return FLOW();
}
void init()
{
}
int main()
{
init();
int kases, kaseno = 0;
int B, D;
int u, v, c;
sf("%d", &kases);
while(kases--)
{
mem(capacity, 0);
sf("%d", &N);
source = 0;
sink = 2*(N + 1); // A number out of the range of node id.
for(int i=0; i<=sink; i++)
{
graph[i].clear();
}
for(int i=1; i<=N; i++)
{
u = 2*i - 1;
v = u + 1;
graph[u].pb(v);
graph[v].pb(u);
sf("%d", &capacity[u][v]);
}
sf("%d", &M);
loop(i, M)
{
sf("%d %d %d", &u, &v, &c);
u = 2*u;
v = 2*v - 1;
graph[u].pb(v);
graph[v].pb(u);
capacity[u][v] = c;
}
sf("%d %d", &B, &D);
loop(i, B)
{
sf("%d", &u);
u = 2*u - 1;
graph.pb(u);
graph[u].pb(source);
capacity[ source ][u] = INF;
}
loop(i, D)
{
sf("%d", &v);
{
v = 2*v;
graph[v].pb(sink);
graph[sink].pb(v);
capacity[v][sink] = INF;
}
}
pf("Case %d: %d\n", ++kaseno, solve());
}
return 0;
}
(UVa) 615 – Is It A Tree?
0
/****************************************************************
▄█ █▄ ▄████████ ▄████████ ▄█ ▀█████████▄
███ ███ ███ ███ ███ ███ ███ ███ ███
███ ███ ███ ███ ███ █▀ ███ ███ ███
▄███▄▄▄▄███▄▄ ███ ███ ███ ███ ▄███▄▄▄██▀
▀▀███▀▀▀▀███▀ ▀███████████ ▀███████████ ███ ▀▀███▀▀▀██▄
███ ███ ███ ███ ███ ███ ███ ██▄
███ ███ ███ ███ ▄█ ███ ███ ███ ███
███ █▀ ███ █▀ ▄████████▀ █▀ ▄█████████▀
****************************************************************/
#include<bits/stdc++.h>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define take(args...) asdf,args
#define dump(x) cerr<<#x<<" = "<<x<<endl
#define debug(args...) cerr,args; cerr<<endl;
using namespace std;
template<typename T>
ostream& operator<<(ostream& output, vector<T>&v)
{
output<<"[ ";
if(SZ(v))
{
output<<v[0];
}
FOR(i, 1, SZ(v))
{
output<<", "<<v[i];
}
output<<" ]";
return output;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& output, pair<T1, T2>&p)
{
output<<"( "<<p.fr<<", "<<p.sc<<" )";
return output;
}
template<typename T>
ostream& operator,(ostream& output, T x)
{
output<<x<<" ";
return output;
}
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
//Header ends here
set<int>NodeList;
set<int>inputNodes;
map<int,int>parent;
int find(int u)
{
if(parent[u] == u) return u;
return parent[u] = find(parent[u]);
}
void init()
{
}
int main()
{
init();
int kaseno = 0;
int p, q;
int edge;
bool possible;
while(true)
{
scanf("%d %d", &p, &q);
if(p < 0 && q < 0)
{
break;
}
else
{
edge = 0;
NodeList.clear();
inputNodes.clear();
parent.clear();
possible = true;
while(p != 0 && q != 0)
{
edge++;
NodeList.insert(p);
NodeList.insert(q);
if(parent[p] == 0)
{
parent[p] = p;
}
if(parent[q] == 0)
{
parent[q] = q;
}
int u = find(p);
int v = find(q);
if(u == v)
{
possible = false;
}
parent[ v ] = u;
if(inputNodes.find(q) != inputNodes.end())
{
possible = false;
}
else
{
inputNodes.insert(q);
}
scanf("%d %d", &p, &q);
}
if( edge == 0 || (possible && (edge == SZ(NodeList) - 1) && (edge == SZ(inputNodes)) ) )
{
pf("Case %d is a tree.\n", ++kaseno);
}
else
{
pf("Case %d is not a tree.\n", ++kaseno);
}
}
}
return 0;
}
D. Hydra (codeforces)
0
//link: http://codeforces.com/contest/244/problem/D
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<vector>
#include<queue>
#include<stack>
#include<map>
#include<utility>
#include<set>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) FOR(i, 0, n)
#define sf scanf
#define pf printf
#define pb push_back
#define MP make_pair
#define fr first
#define sc second
#define ll long long
#define dd double
#define all(v) v.begin(), v.end()
#define PI acos(-1.0)
#define mem(ara, value) memset(ara, value, sizeof(ara))
#define paii pair<int, int>
#define pall pair<ll, ll>
#define SZ(a) int(a.size())
#define read(nm) freopen(nm, "r", stdin)
#define write(nm) freopen(nm, "w", stdout)
#define dump(x) cout<<#x<<" = "<<x<<endl
using namespace std;
#define take(args...) asdf,args
#define debug(args...) asdfg,args; cout<<endl
struct ASDF{
ASDF& operator,(int &a) {
sf("%d", &a);
return *this;
}
ASDF& operator,(long int &a){
sf("%ld", &a);
return *this;
}
ASDF& operator,(long long int &a){
sf("%lld", &a);
return *this;
}
ASDF& operator,(char &c){
sf("%c", &c);
return *this;
}
ASDF& operator,(double &d){
sf("%lf", &d);
return *this;
}
template<typename T>
ASDF& operator,(T &a){
cin>>a;
return *this;
}
}asdf;
struct ASDFG{
template<typename T>
ASDFG& operator,(vector<T> &v){
pf("[");
cout<<v[0];
FOR(i, 1, SZ(v)){
cout<<", "<<v[i];
}
pf("]");
return *this;
}
template<typename T>
ASDFG& operator,(T x) {
cout<<x<<" ";
return *this;
}
}asdfg;
//Header ends here
#define MAXX 100004
int deg[MAXX];
vector<paii> edges;
int h, t;
vector<int>graph[MAXX];
int isAchived[MAXX];
int isValid(int u, int v)
{
if(deg[u] < h+1 || deg[v] < t+1 )
{
return 0;
}
loop(i, SZ(graph[u]))
{
isAchived[ graph[u][i] ]++;
}
int duplicate = 0;
loop(i, SZ(graph[v]))
{
if(isAchived[ graph[v][i] ])
{
duplicate++;
isAchived[graph[v][i] ]++;
}
}
if(deg[u] + deg[v] - duplicate - 2 >= h+t)
{
return 1;
}
else
{
loop(i, SZ(graph[u])) isAchived[ graph[u][i] ] = 0;
return 0;
}
}
void generateSolution(int u, int v)
{
vector<int>v1, v2, com;
loop(i, SZ(graph[u]))
{
if(graph[u][i] == v) continue;
if(isAchived[ graph[u][i] ] == 1 )
{
v1.pb( graph[u][i] );
}
else
{
com.pb(graph[u][i]);
}
}
loop(i, SZ(graph[v]))
{
if(graph[v][i] == u) continue;
if( isAchived[ graph[v][i] ] == 0 )
{
v2.pb(graph[v][i]);
}
}
int pos = 0;
while(SZ(v1) < h)
{
v1.pb(com[pos++]);
}
while(SZ(v2) < t)
{
v2.pb(com[pos++]);
}
pf("YES\n");
pf("%d %d\n", u, v);
pf("%d", v1[0]);
FOR(i,1,h)
{
pf(" %d", v1[i]);
}
pf("\n");
pf("%d", v2[0]);
FOR(i,1,t)
{
pf(" %d", v2[i]);
}
pf("\n");
}
int main()
{
int n, m, u, v;
take(n, m, h, t);
loop(i, m)
{
take(u, v);
edges.pb(MP(u, v));
deg[u]++; deg[v]++;
graph[u].pb(v); graph[v].pb(u);
}
bool possible = false;
loop(i, m)
{
if(isValid(edges[i].fr, edges[i].sc))
{
possible = 1;
generateSolution(edges[i].fr, edges[i].sc);
break;
}
else if(isValid(edges[i].sc, edges[i].fr))
{
possible=1;
generateSolution(edges[i].sc, edges[i].fr);
break;
}
}
if(!possible) cout<<"NO\n";
}
UnLucky Codes 