hdu4307 Matrix 最小割

...其實SAP也可以寫的很短！！，不考慮bfs優化的話20行代碼... 

#include<iostream>
#include<cstdio>
#include<string>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<queue>
using namespace std;
const int inf=0x3fffffff;
const int maxn=1005;
struct edge
{
    int to,ec,next,rev;
}ee[maxn*maxn*2];
int e[maxn],ecnt;
int st,ed,d[maxn],gap[maxn],n,m;
queue<int> q;
bool inq[maxn];
void addedge(int u,int v,int c)
{
    ee[ecnt].to=v;ee[ecnt].ec=c;ee[ecnt].next=e[u];ee[ecnt].rev=ecnt+1;e[u]=ecnt++;
    ee[ecnt].to=u;ee[ecnt].ec=0;ee[ecnt].next=e[v];ee[ecnt].rev=ecnt-1;e[v]=ecnt++;
}
void bfs()
{
    while(!q.empty())
        q.pop();
    int i,u,v,c;
    memset(inq,false,sizeof(inq));
    memset(gap,0,sizeof(gap));
    memset(d,0,sizeof(d));
    q.push(ed);d[ed]=0;inq[ed]=true;
    while(!q.empty())
    {
        u=q.front();q.pop();
        for(i=e[u];i!=-1;i=ee[i].next)
        {
            v=ee[i].to;c=ee[i].ec;
            if(c==0&&!inq[v])
            {
                q.push(v);inq[v]=true;
                d[v]=d[u]+1;
            }
        }
    }
    for(i=0;i<n;++i)
        gap[d[i]]++;
}
int sap(int u,int flow)
{
    if(u==ed)
        return flow;
    int i,res=flow,v,c,t;
    for(i=e[u];i!=-1;i=ee[i].next)
    {
        v=ee[i].to;c=ee[i].ec;
        if(c>0&&d[u]==d[v]+1)
        {
            t=sap(v,min(res,c));
            ee[i].ec-=t;ee[ee[i].rev].ec+=t;
            if(!(res-=t))
                return flow;
        }
    }
    if(!--gap[d[u]])
        d[st]=n;
    ++gap[++d[u]];
    return flow-res;
}
int main()
{
    int t,i,j,u,v,c,sum,ans,tot,x;
    scanf("%d",&t);
    while(t--)
    {
        memset(e,-1,sizeof(e));ecnt=0;
//        memset(d,0,sizeof(d));
//        memset(gap,0,sizeof(gap));
        scanf("%d",&n);
        ans=0;tot=0;
        st=0;ed=n+1;
        for(i=1;i<=n;++i)
        {
            sum=0;
            for(j=1;j<=n;++j)
            {
                scanf("%d",&x);
                sum+=x;
                addedge(i,j,x);
            }
            tot+=sum;
            addedge(st,i,sum);
        }
        for(i=1;i<=n;++i)
        {
            scanf("%d",&x);
            addedge(i,ed,x);
        }
        n+=2;
        for(bfs();d[st]<n;)
//        for(gap[0]=n;d[st]<n;)
            ans+=sap(st,inf);
        printf("%d\n",tot-ans);
    }
    return 0;
}