比较简单。

#include
     
      #include
      
       #include
       
        #define maxn 110#define INF 99999999using namespace std;int vis[maxn],n,map[maxn][maxn];int min(int x,int y){
    return x
        
         0)        {            a=dfs(i,min(low,map[u][i]));            if(!a)continue;            map[u][i]-=a;            map[i][u]+=a;            return a;        }    }    return 0;}bool BFS(){    int i;    queue
         
          q;    memset(vis,-1,sizeof(vis));    vis[0]=0;    q.push(0);    while(!q.empty())    {        int t=q.front();        q.pop();        for(i=0;i<=n+1;i++)        {            if(vis[i]<0&&map[t][i]>0)            {                vis[i]=vis[t]+1;                q.push(i);            }        }    }    if(vis[n+1]>0)return true;    return false;}int main(){    int i,nc,np,m;    while(scanf("%d %d %d %d",&n,&np,&nc,&m)!=EOF)    {        memset(map,0,sizeof(map));        for(i=0;i