hihoCoder 1393 网络流三·二分图多重匹配 (网络流学习#3 记录）

#include<cstdio>
#include<cstring>
#include<queue>
using namespace std;
const int N=205;
struct ss{
int v,c,nxt;
} e[N*20];
int head[N],tot,vis[N],n,m,a[N],b[N],sum,INF=0x3f3f3f3f,t;
queue<int>q;
void add(int u,int v,int c)
{
    e[tot].c=c;
    e[tot].v=v;
    e[tot].nxt=head[u];
    head[u]=tot++;

    e[tot].c=0;
    e[tot].v=u;
    e[tot].nxt=head[v];
    head[v]=tot++;
}
bool bfs()
{
    memset(vis,0,sizeof(vis));
    vis[0]=1;
    q.push(0);
    int tmp,id;
    while(!q.empty())
    {
        tmp=q.front();
        q.pop();
        for(int i=head[tmp]; i!=-1; i=e[i].nxt)
        {
            id=e[i].v;
            if(vis[id]==0&&e[i].c)
                vis[id]=vis[tmp]+1,q.push(id);
        }
    }
    return vis[n+m+1];
}
int dfs(int node,int c)
{
    if(node==t||c==0)
        return c;
    int ans=0;
    for(int i=head[node]; i!=-1; i=e[i].nxt)
    {
        int id=e[i].v,kk;
        if(vis[id]==vis[node]+1)
        {
            kk=dfs(id,min(c,e[i].c));
            if(kk>0)
            {
                e[i].c-=kk;
                e[i^1].c+=kk;
                ans+=kk;
                c-=kk;
                if(c==0)
                    return ans;
            }
        }
    }
    return ans;
}
int mf()
{
    int ans=0;
    while(bfs())
    {
        ans+=dfs(0,INF);
    }
    if(ans!=sum)
        return 0;
    return 1;
}
int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {

        int x=0;
        memset(head,-1,sizeof(head));
        tot=0;
        sum=0;
        scanf("%d%d",&n,&m);
        t=n+m+1;
        for(int i=1; i<=m; i++)
        {
            scanf("%d",&x);
            add(n+i,t,x);
            sum+=x;
        }
        for(int i=1; i<=n; i++)
        {
            scanf("%d%d",&a[i],&b[i]);
            add(0,i,a[i]);
            for(int j=0; j<b[i]; j++)
            {
                scanf("%d",&x);
                add(i,x+n,1);
            }
        }
        if(mf())
            puts("Yes");
        else
            puts("No");
    }
}

#include<bits/stdc++.h>
using namespace std;
const int maxn=205,INF=0x3f3f3f3f;

int n,m,a[maxn],b[maxn],mm[maxn],s=0,t,c[maxn][maxn],pre[maxn],flow[maxn];
int bfs()
{
    int tmp;
    memset(pre,-1,sizeof(pre));
    memset(flow,0,sizeof(flow));
    queue<int>q;
    q.push(s);
    flow[s]=INF;
    while(!q.empty())
    {
        tmp=q.front();
        q.pop();
        if(tmp==t)
            return flow[t];
        for(int i=1;i<=t;i++)
        {
            if(pre[i]==-1&&c[tmp][i]>0)
            {
                pre[i]=tmp;
                flow[i]=min(flow[tmp],c[tmp][i]);
                if(flow[i]!=0)
                    q.push(i);
            }
        }
    }
    return 0;
}
void work()
{
    int ans=0;
    int tmp;
    while(bfs())
    {
        tmp=t;
        while(tmp!=s)
        {
            c[pre[tmp]][tmp]-=flow[t];
            c[tmp][pre[tmp]]+=flow[t];
            tmp=pre[tmp];
        }
        ans+=flow[t];
    }
    if(ans!=mm[0])
        puts("No");
    else
        puts("Yes");
}
int main()
{
    int T,tmp;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d%d",&n,&m);
        t=n+m+1;
        mm[0]=0;
        memset(c,0,sizeof(c));
        for(int i=1;i<=m;i++)
        {
            scanf("%d",&mm[i]);
            c[n+i][t]+=mm[i];
            mm[0]+=mm[i];
        }
        for(int i=1;i<=n;i++)
        {
            scanf("%d%d",&a[i],&b[i]);
            c[s][i]+=a[i];
            for(int j=1;j<=b[i];j++)
            {
                scanf("%d",&tmp);
                c[i][n+tmp]+=1;
            }
        }
        work();
    }
}