/***********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 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;
}
};
vector<int>original[NODE], modified[NODE];
int orgN, modN;
bool orgVisited[NODE], modVisited[NODE];
bool isMatch[NODE][NODE];
bool match(int u, int v)
{
orgVisited[u] = modVisited[v] = true;
int uu, vv;
KUHN kuhn;
/// !wow! Got WA because I took kuhn as local variable, and didn't clear visited!
mem(kuhn.vis, 0);
kuhn.clear(NODE-1);
loop(i, SZ(original[u]))
{
uu = original[u][i];
if(orgVisited[uu]) continue;
loop(j, SZ(modified[v]))
{
vv = modified[v][j];
if(modVisited[vv]) continue;
if(match(uu, vv))
{
kuhn.adj[i].pb(j);
}
}
}
orgVisited[u] = modVisited[v] = false;
int m = kuhn.match( SZ(original[u]) + 2 );
int child = SZ(original[u]) - 1;
if(u == 1) child++;
bool ret = (m == child);
return ret;
}
void solve()
{
//mem(orgVisited, 0); ///
//mem(modVisited, 0); ///
bool ret = match(1, 1);
if(ret)
{
pf("Yes\n");
}
else
{
pf("No\n");
}
}
int main ()
{
#ifdef hasibpc
read("input.txt");
//write("output.txt");
#endif // hasibpc
int kases, kaseno = 0;
int u, v;
sf("%d", &kases);
while(kases--)
{
sf("%d", &modN);
FOR(i, 0, modN) modified[i].clear();
for(int i=1; i<modN; i++)
{
sf("%d %d", &u, &v);
//debug(u, v);
modified[u].pb(v);
modified[v].pb(u);
}
//vdump(endl);
sf("%d", &orgN);
FOR(i, 0, orgN) original[i].clear();
for(int i=1; i<orgN; i++)
{
sf("%d %d", &u, &v);
//debug(u, v);
original[u].pb(v);
original[v].pb(u);
}
pf("Case %d: ", ++kaseno);
solve();
}
return 0;
}
Category Archives: DFS
(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);
}
}
}
(UVa) 572 – Oil Deposits
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 107
int rows, columns;
char graph[MAXX][MAXX];
bool visited[MAXX][MAXX];
int component;
int dx[] = {-1, -1, -1, 0, 0, 1, 1, 1};
int dy[] = {-1, 0, 1, -1, 1, -1, 0, 1};
void dfs(paii u)
{
visited[u.fr][u.sc] = true;
paii v;
loop(i, 8)
{
v = MP(u.fr + dx[i], u.sc + dy[i]);
if(0<=v.fr && v.fr <rows && 0<= v.sc && v.sc <columns)
{
if( ! visited[v.fr][v.sc] && graph[v.fr][v.sc] == '@' )
{
dfs(v);
}
}
}
}
void solve()
{
mem(visited, 0);
component = 0;
loop(i, rows)
{
loop(j, columns)
{
if(!visited[i][j] && graph[i][j] == '@')
{
component++;
dfs(MP(i, j));
}
}
}
}
int main()
{
while(true)
{
sf("%d %d", &rows, &columns);
if(rows == 0) break;
loop(i, rows)
{
sf("%s", graph[i]);
}
solve();
//dump(component);
pf("%d\n", component);
}
}
(USACO) Humble Numbers
0
// link: http://cerberus.delos.com:790/usacoprob2?a=VKy6gbSa7gv&S=humble
/*
ID: himuhas1
TASK: humble
LANG: C++
*/
#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 MAX_PRIMES 102
#define MAX_N 100002
#define INF 4611686018427387904
int primes[MAX_PRIMES];
int hprime[MAX_PRIMES];
long long humble[MAX_N];
int main()
{
#ifndef hasibpc
read("humble.in");
write("humble.out");
#endif
int cntPrime, N;
take(cntPrime, N);
long long temp;
loop(i, cntPrime)
{
take(primes[i]);
}
mem(hprime, 0);
humble[0] = 1;
loop(i, N)
{
long long next = INF;
loop(p, cntPrime)
{
while(primes[p]*humble[ hprime[p] ] <= humble[i])
{
hprime[p]++;
}
temp = primes[p]*humble[ hprime[p] ];
if(temp < next)
{
next = temp;
}
}
humble[i+1] = next;
}
cout<<humble[N]<<endl;
return 0;
}
(USACO) Controlling Companies
0
/*
ID: himuhas1
TASK: concom
LANG: C++
*/
#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 gi(a) sf("%d", &a)
#define gi2(a, b) sf("%d%d", &a, &b)
#define gi3(a, b, c) sf("%d %d %d", &a, &b, &c)
#define gi4(a, b, c, d) sf("%d%d%d%d", &a, &b, &c, &d)
#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 freopen("input.txt", "r", stdin)
#define write freopen("output.txt", "w", stdout)
using namespace std;
#define MAXX 101
vector<paii>graph[MAXX];
set<int>allNodes;
vector<int> result;
bool visited[MAXX];
int rank[MAXX];
void dfs(int source)
{
visited = 1;
loop(i, SZ(graph))
{
if(!visited[graph[i].fr])
{
rank[ graph[i].fr ] += graph[i].sc;
if(rank[graph[i].fr] > 50)
{
result.pb(graph[i].fr);
dfs(graph[i].fr);
}
}
}
}
int main()
{
#ifndef hasibpc
freopen("concom.in", "r", stdin);
freopen("concom.out", "w", stdout);
#endif // hasibpc
int connection;
int p, q, r;
gi(connection);
loop(i, connection)
{
gi3(p, q, r);
allNodes.insert(p);
allNodes.insert(q);
graph[p].pb(MP(q, r));
}
for(set<int>::iterator it=allNodes.begin(); it != allNodes.end(); it++)
{
result.clear();
mem(visited, 0);
mem(rank, 0);
dfs(*it);
sort(all(result));
loop(i, SZ(result))
{
pf("%d %d\n", *it, result[i]);
}
}
return 0;
}
(UVa) 247 – Calling Circles
0
/*
user: php
link: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=183
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<vector>
#include<string>
#include<stack>
#include<queue>
#include<map>
#include<sstream>
#include<utility>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) for(int i=0; i<n; i++)
#define getint(n) scanf("%d", &n)
#define pb(a) push_back(a)
#define ll long long
#define dd double
#define SZ(a) int(a.size())
#define read() freopen("input.txt", "r", stdin)
#define write() freopen("output.txt", "w", stdout)
#define mem(a, v) memset(a, v, sizeof(a))
#define all(v) v.begin(), v.end()
#define pi acos(-1.0)
#define INF 1<<29
#define mod abs
#define pf printf
#define sf scanf
#define mp make_pair
#define paii pair<int, int>
#define padd pair<dd, dd>
#define pall pair<ll, ll>
#define fr first
#define sc second
using namespace std;
#define MAXX 27
int n, m;
map<string, int>pos;
vector<int>graph[MAXX];
string names[MAXX];
bool possible[MAXX][MAXX];
bool used[MAXX];
void dfs(int u, int v)
{
possible[u][v] = 1;
loop(i, SZ(graph[v]))
{
if(!possible[u][ graph[v][i] ])
{
dfs(u, graph[v][i] );
}
}
}
int main()
{
//read();
int kaseno = 0;
int id;
int *p, *q;
char fname[MAXX], lname[MAXX];
string fffname, lllname;
while(1)
{
getint(n); getint(m);
id = 0;
if(n+m == 0) break;
pos.clear();
for(int i=1; i<=n; i++) graph[i].clear();
loop(i, m)
{
sf("%s %s", fname, lname);
fffname = fname;
lllname = lname;
p = &pos[fffname];
if(*p == 0)
{
*p = ++id;
names[*p] = fffname;
}
q = &pos[lllname];
if(*q == 0)
{
*q = ++id;
names[*q] = lllname;
}
graph[*p].pb(*q);
}
mem(possible, 0);
mem(used, 0);
for(int i=1; i<=n; i++)
{
dfs(i, i);
}
if(kaseno) pf("\n");
pf("Calling circles for data set %d:\n", ++kaseno);
for(int i=1; i<=n; i++)
{
if(used[i]) continue;
used[i] = 1;
pf("%s", names[i].c_str() );
for(int j=1; j<=n; j++)
{
if(!used[j] && possible[i][j] && possible[j][i])
{
pf(", %s", names[j].c_str());
//pf(", %d", j);
used[j] = 1;
}
}
pf("\n");
}
}
return 0;
}
(UVa) 11709 – Trust groups
0
/*
user: php
link: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=2756
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<vector>
#include<string>
#include<stack>
#include<queue>
#include<map>
#include<sstream>
#include<utility>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) for(int i=0; i<n; i++)
#define getint(n) scanf("%d", &n)
#define pb(a) push_back(a)
#define ll long long
#define dd double
#define SZ(a) int(a.size())
#define read() freopen("input.txt", "r", stdin)
#define write() freopen("output.txt", "w", stdout)
#define mem(a, v) memset(a, v, sizeof(a))
#define all(v) v.begin(), v.end()
#define pi acos(-1.0)
#define INF 1<<29
#define mod abs
#define pf printf
#define sf scanf
#define mp make_pair
#define paii pair<int, int>
#define padd pair<dd, dd>
#define pall pair<ll, ll>
#define fr first
#define sc second
using namespace std;
#define MAXX 1002
map<string, int> mapping;
vector<int>graph[MAXX];
bool visited[MAXX][MAXX];
bool used[MAXX];
int P, T;
void dfs(int u, int v)
{
visited[u][v] = 1;
int vv;
loop(i, SZ(graph[v]))
{
vv = graph[v][i];
if(!visited[u][vv])
{
dfs(u, vv);
}
}
}
int main()
{
//string str1, str2;
char finput[25], sinput[25];
int cnt;
while(1)
{
getint(P); getint(T);
if(P == 0 && T == 0) break;
mapping.clear();
cin.ignore();
loop(i, P)
{
graph[i].clear();
//getline(cin, str1);
gets(finput);
mapping[finput] = i;
}
loop(i, T)
{
//getline(cin, str1);
//getline(cin, str2);
gets(finput);
gets(sinput);
graph[ mapping[finput] ].pb(mapping[sinput]);
}
mem(visited, 0);
loop(i, P) dfs(i, i);
mem(used, 0);
cnt = 0;
loop(i, P)
{
if(!used[i])
{
cnt++;
FOR(j, i+1, P)
{
if( !used[j] && visited[i][j] && visited[j][i] )
{
used[j] = 1;
}
}
}
}
pf("%d\n", cnt);
}
return 0;
}
(UVa) 10308 – Roads in the North
0
/*
user: php
time: 0.304 sec
link: http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=1249
*/
#include<iostream>
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<algorithm>
#include<vector>
#include<string>
#include<stack>
#include<queue>
#include<map>
#include<sstream>
#define FOR(i, s, e) for(int i=s; i<e; i++)
#define loop(i, n) for(int i=0; i<n; i++)
#define getint(n) scanf("%d", &n)
#define pb(a) push_back(a)
#define ll long long
#define SZ(a) int(a.size())
#define read() freopen("input.txt", "r", stdin)
#define write() freopen("output.txt", "w", stdout)
#define mem(a, v) memset(a, v, sizeof(a))
#define all(v) v.begin(), v.end()
#define pi acos(-1.0)
#define INF 1<<29
#define mod(a) (a>0?a:-a)
#define pf printf
#define sf scanf
using namespace std;
#define MAXX 10002
vector<int>graph[MAXX];
int cost[MAXX][MAXX];
ll dist[MAXX];
bool visited[MAXX];
int farnode1;
ll bfs(int u)
{
mem(visited, false);
queue<int>Q;
ll maxdist = 0;
visited[u] = 1;
Q.push(u);
dist[u] = 0;
int v;
int len;
while( !Q.empty() )
{
u = Q.front();
if(dist[u] > maxdist)
{
maxdist = dist[u];
farnode1 = u;
}
len = SZ(graph[u]);
loop(i, len)
{
v = graph[u][i];
if(!visited[v])
{
visited[v] = 1;
dist[v] = dist[u] + cost[u][v];
Q.push(v);
}
}
Q.pop();
}
return maxdist;
}
int main()
{
//read();
int p, q, cst;
string str;
stringstream ss;
while( ! cin.eof() )
{
getline(cin, str);
if(str == "")
{
pf("0\n");
getline(cin, str);
continue;
}
loop(i, MAXX) graph[i].clear();
while( !cin.eof() && SZ(str) > 0 )
{
if(str == "") break;
ss.clear();
ss<<str;
ss>>p>>q>>cst;
graph[p].pb(q);
graph[q].pb(p);
cost[p][q] = cst;
cost[q][p] = cst;
getline(cin, str);
}
bfs(1);
pf("%lld\n", bfs(farnode1));
}
return 0;
}
UnLucky Codes 