HDU 1151

来源：互联网发布：淘宝发布虚拟物品编辑：程序博客网时间：2024/06/14 19:20

分析：二分匹配，二分图最小路径覆盖=点的个数-最大匹配

#include <iostream>#include<cstdio>#include<cstring>#include<algorithm>#include<string>#define maxn 125using namespace std;int n,m,w[maxn][maxn];int linker[maxn];bool used[maxn];bool dfs(int u){    int v;    for(v=1;v<=n;v++)    if(w[u][v]&&!used[v])    {        used[v]=true;        if(linker[v]==-1||dfs(linker[v]))        {            linker[v]=u;            return true;        }    }    return false;}int hungary(){    int res=0;    int u=0;    memset(linker,-1,sizeof(linker));    for(u=1;u<=n;u++)    {        memset(used,0,sizeof(used));        if(dfs(u))        res++;    }    return res;}int main(){    int t,k,i,j,tmp;    scanf("%d",&t);    while(t--)    {        scanf("%d%d",&n,&k);        memset(w,0,sizeof(w));        while(k--)        {            scanf("%d%d",&i,&j);            w[i][j]=1;        }        printf("%d\n",n-hungary());    }    return 0;}