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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
const int MaxN=1005, Inf=0x3f3f3f3f;
int N,M;
vector<int> G[MaxN];
int C[MaxN][MaxN];
void Read();
bool Drum(vector<int> G[], int N, int C[MaxN][MaxN], int F[MaxN][MaxN], int P[], bool V[]);
int Flux(vector<int> G[], int N, int C[MaxN][MaxN]);
int main()
{
Read();
fout<<Flux(G,N,C)<<'\n';
fout.close();
return 0;
}
void Read()
{
fin>>N>>M;
int x,y,z;
while(M--)
{
fin>>x>>y>>z;
G[x].push_back(y);
C[x][y]=z;
C[y][x]=0;
}
fin.close();
}
bool Drum(vector<int> G[], int N, int C[MaxN][MaxN], int F[MaxN][MaxN], int P[], bool V[])
{
for(int i=2;i<=N;++i)
V[i]=false;
queue<int> Q;
Q.push(1);
while(!Q.empty())
{
int nod=Q.front();
Q.pop();
if(nod==N) continue;
vector<int>::iterator i;
for(i=G[nod].begin();i!=G[nod].end();++i)
if(F[nod][*i]<C[nod][*i] && !V[*i])
{
P[*i]=nod;
Q.push(*i);
V[*i]=true;
}
}
return V[N];
}
int Flux(vector<int> G[], int N, int C[MaxN][MaxN])
{
int F[MaxN][MaxN],P[MaxN];
bool V[MaxN];
V[1]=true;
for(int i=1;i<=N;++i)
for(int j=1;j<=N;++j)
F[i][j]=0;
P[1]=0;
int flux_total=0;
while(Drum(G,N,C,F,P,V))
{
vector<int>::iterator i;
for(i=G[N].begin();i!=G[N].end();++i)
if(F[*i][N]<C[*i][N] && V[*i])
{
P[N]=*i;
int minim=Inf;
for(int x=N;x!=1;x=P[x])
if(C[P[x]][x]-F[P[x]][x]<minim)
minim=C[P[x]][x]-F[P[x]][x];
if(!minim) continue;
flux_total+=minim;
for(int x=N;x!=1;x=P[x])
{
F[P[x]][x]+=minim;
F[x][P[x]]-=minim;
}
}
}
return flux_total;
}