【最小路徑覆蓋模板題】POJ 1422

#include <map>#include <set>#include <list>#include <queue>#include <deque>#include <stack>#include <string>#include <cstdio>#include <math.h>#include <iomanip>#include <cstdlib>#include <limits.h>#include <string.h>#include <iostream>#include <fstream>#include <algorithm>using namespace std;#define LL long long#define MIN -99999999#define MAX 99999999#define pii pair<int ,int>#define bug cout<<"here!!"<<endl#define PI acos(-1.0)#define FRE freopen("input.txt","r",stdin)#define FF freopen("output.txt","w",stdout)#define eps 1e-8#define N 122int match[N];bool vis[N];int g[N][N];int n;bool sear(int s){    int i,j;    for(i=1;i<=n;i++){        if(g[i][s] && !vis[i]){            vis[i] = 1;            if(match[i] == 0 || sear(match[i])){                match[i] = s;                return true;            }        }    }    return false;}int main(){    int t;    scanf("%d",&t);    while(t--){        int m;        scanf("%d%d",&n,&m);        int i,j;        int a,b;        memset(g,0,sizeof(g));        memset(match,0,sizeof(match));        while(m--){            scanf("%d%d",&a,&b);            g[a][b] = 1;        }        int cnt = 0;        for(i=1;i<=n;i++){            memset(vis,0,sizeof(vis));            if(sear(i))cnt++;        }        printf("%d\n",n-cnt);    }    return 0;}