POJ1469[COURSES] 二分图最大匹配 匈牙利算法

题目链接

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题意：题目大意：将vy个工作分配给vx个学生，求能不能每个同学都有分配到工作。

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解题思路：二分图匹配，看匹配数是否等于课程数

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#include <cstdio>#include <iostream>#include <cstring>#include <algorithm>using namespace std;const int N = 305;const int P = 105;int T[N], line[N], w[P][N];int p, n;bool find(int u){    for ( int i=1; i<=n; i++ )        if( !T[i] && w[u][i] ){            T[i]=1;            if( !line[i] || find(line[i]) ){                line[i]=u;                return true;            }        }    return false;} int Hungarian(){    int ans=0;    memset(line,0,sizeof(line));    for ( int i=1; i<=p; i++ ){        memset(T,0,sizeof(T));        if( find(i) ) ans++;    }    return ans;}int main(){    int tt;    scanf("%d", &tt );    while( tt-- ){        memset(w,0,sizeof(w));        scanf("%d%d", &p, &n );        for ( int i=1; i<=p; i++ ){            int x;            scanf("%d", &x );            for ( int j=1; j<=x; j++ ){                int v;                scanf("%d", &v );                w[i][v]=1;            }        }        (Hungarian()==p) ? puts("YES") : puts("NO");     }}