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#include <fstream>
#include <vector>
#include <queue>
#include <algorithm>
using namespace std;
#define NMax 1005
#define inf 2100000000
ifstream f("maxflow.in");
ofstream g("maxflow.out");
int n,m;
vector<int> v[NMax];
int C[NMax][NMax],F[NMax][NMax];
int viz[NMax],ant[NMax];
int Lant(int s)
{
int a=inf,b=inf,val;
int nod2,nod=s;
while(ant[nod])
{
nod2=abs(ant[nod]);
if(ant[nod]>0) a=min(a,C[nod2][nod]-F[nod2][nod]);
else b=min(b,F[nod][nod2]);
nod=nod2;
}
val=min(a,b);
nod=s;
while(ant[nod])
{
nod2=abs(ant[nod]);
if(ant[nod]>0) F[nod2][nod]+=val;
else F[nod][nod2]-=val;
nod=nod2;
}
F[s][n]+=val;
return val;
}
int BFS()
{
int s,i,semn;
queue<int> cd;
cd.push(1);
for(i=1;i<=n;i++) {viz[i]=ant[i]=0;}
viz[1]=1;
while(!cd.empty())
{
s=cd.front(); cd.pop();
for(i=0;i<(int)v[s].size();i++) if(!viz[v[s][i]])
{
semn=0;
if(F[s][v[s][i]]<C[s][v[s][i]]) semn=1;
else if(!C[s][v[s][i]] && F[s][v[s][i]]) semn=-1;
if(semn)
{
viz[v[s][i]]=1;
ant[v[s][i]]=semn*s;
if(v[s][i]!=n) cd.push(v[s][i]);
}
}
}
return viz[n];
}
int main()
{
int i,a,b,c;
int flow;
f>>n>>m;
for(i=1;i<=m;i++)
{
f>>a>>b>>c;
C[a][b]=c;
v[a].push_back(b);
v[b].push_back(a);
}
for(flow=0;BFS();)
for(i=0;i<(int)v[n].size();i++)
flow+=Lant(v[n][i]);
g<<flow<<"\n";
f.close();
g.close();
return 0;
}