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#include<bits/stdc++.h>

using namespace std;

#define M 10001

#define inf 1000000

int ip=1,head[M],lv[M];

int s,T;

struct E{

    int to,next,cap;

}e[M*10];

void add(int x,int y,int z){

    e[++ip].to=y;e[ip].next=head[x];e[ip].cap=z;head[x]=ip;

    e[++ip].to=x;e[ip].next=head[y];e[ip].cap=0;head[y]=ip;

}

bool bfs(){

    memset(lv,-1,sizeof(lv));

    queue<int> q;

    q.push(s);

    lv[s]=0;

    while(!q.empty()){

        int t=q.front();

        q.pop();

        for(int i=head[t];i;i=e[i].next){

            if(lv[e[i].to]==-1&&e[i].cap){

                lv[e[i].to]=lv[t]+1;

                q.push(e[i].to);

            }

        }

    }

    return lv[T]!=-1;

}

 

int dfs(int u,int f){

    if(u==T||f==0)return f;

    int ret=0;

    for(int i=head[u];i;i=e[i].next){

        if(lv[e[i].to]==lv[u]+1&&e[i].cap){

            int w=dfs(e[i].to,min(f,e[i].cap));

            e[i].cap-=w;

            e[i^1].cap+=w;

            f-=w;

            ret+=w;

        }

    }

    if(!ret)lv[u]=-1;

    return ret;

}

int dinic(){

     

    int ans=0;

    while(bfs()){

        ans+=dfs(s,inf);

        //cout<<ans<<endl;

    }

    return ans;

}