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#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
const int VAL=1005;
const int INF=1000000000;
int N, M, i, j, A, B, prec[VAL], nod;
int Capacity[VAL][VAL], Flow, mn;
bool viz[VAL];
queue <int> Q;
vector <int> G[VAL];
vector <int> :: iterator it;
bool BFS()
{
for (i=1; i<=N; i++)
{
prec[i]=0;
viz[i]=false;
}
Q.push(1);
viz[1]=true;
while (Q.empty()==false)
{
nod=Q.front();
Q.pop();
if (nod==N)
continue;
for (it=G[nod].begin(); it!=G[nod].end(); it++)
{
if (viz[*it]==false && Capacity[nod][*it]>0)
{
viz[*it]=true;
prec[*it]=nod;
Q.push(*it);
}
}
}
return viz[N];
}
void Ford_Fulkerson()
{
while (BFS()==true)
{
mn=INF;
nod=N;
while (1)
{
mn=min(mn, Capacity[prec[nod]][nod]);
nod=prec[nod];
if (nod==1)
break;
}
Flow+=mn;
nod=N;
while (1)
{
Capacity[prec[nod]][nod]-=mn;
Capacity[nod][prec[nod]]+=mn;
nod=prec[nod];
if (nod==1)
break;
}
}
}
int main()
{
fin >> N >> M;
for (i=1; i<=M; i++)
{
fin >> A >> B >> Capacity[A][B];
G[A].push_back(B);
G[B].push_back(A);
}
Ford_Fulkerson();
fout << Flow << '\n';
fin.close();
fout.close();
return 0;
}