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#include <fstream>
#include <vector>
#include <queue>
#include <string.h>
#define nmax 1001
using namespace std;
vector<vector<int> > graf;
queue<int>q;
int n,m,source,sink,oo=110000,from[nmax],isVisited[nmax],cap[nmax][nmax],flux[nmax][nmax];
int minim(int a, int b)
{
if(a>b)return b;
return a;
}
int findpath()
{
int CN,i,ln,minCap=oo;
bool isPath;
q.push(source);
isPath=false;
memset(isVisited, 0, sizeof(isVisited));
isVisited[source]=1;
while(!q.empty() && !isPath)
{
CN=q.front();q.pop();
ln=graf[CN].size();
for(i=0;i<ln;i++)
{
if( cap[CN][ graf[CN][i] ] - flux[CN][ graf[CN][i] ] > 0 && !isVisited[graf[CN][i]])
{
from[graf[CN][i]] = CN;
if(graf[CN][i]==sink){isPath=true;break;}
q.push(graf[CN][i]);
isVisited[graf[CN][i]]=1;
}
}
}
while(!q.empty()) q.pop();
if(!isPath)return 0;
CN=sink;
while(CN!=source)
{
minCap=minim(minCap,cap[from[CN]][CN]-flux[from[CN]][CN]);
CN=from[CN];
}
CN=sink;
while(CN!=source)
{
flux[from[CN]][CN]+=minCap;
flux[CN][from[CN]]-=minCap;
CN=from[CN];
}
return minCap;
}
int maxflow()
{
int r=0,res=0;
do
{
res=findpath();
r+=res;
}while(res);
return r;
}
int main()
{
ifstream f("maxflow.in");
ofstream g("maxflow.out");
int i,u,v,c;
f>>n>>m;
graf.resize(n+1);
for(i=1;i<=m;i++)
{
f>>u>>v>>c;
graf[u].push_back(v);
graf[v].push_back(u);
cap[u][v]+=c;
}
source=1;sink=n;
g<<maxflow();
return 0;
}