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#include <bits/stdc++.h>
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
struct elem
{
int nod, poz;
};
int cnt=0;
vector <elem> v[1009];
bool viz[1009];
queue <int> q;
int s, d, sol=0, n;
elem tata[10009];
int r[10009];
bool bfs ()
{
for (int i=1; i<=n; i++)
viz[i]=0, tata[i]={0, 0};
q.push(s);
viz[s]=1;
while (!q.empty())
{
int x=q.front();
q.pop();
for (auto y:v[x])
{
if (!viz[y.nod] && r[y.poz]>0)
{
viz[y.nod]=1;
tata[y.nod].nod=x;
tata[y.nod].poz=y.poz;
q.push(y.nod);
}
}
}
return viz[d];
}
void flux_maxim ()
{
int flow=0;
while (bfs())
{
for (auto y:v[d])
{
if ((tata[y.nod].nod!=0 || y.nod==s) && r[y.poz^1]>0)
{
flow=r[y.poz^1];
for (int j=y.nod; j!=s; j=tata[j].nod)
{
flow=min (flow, r[tata[j].poz]);
if (!flow)
break;
}
if (flow)
{
r[y.poz^1]-=flow;
r[y.poz]+=flow;
for (int j=y.nod; j!=s; j=tata[j].nod)
{
r[tata[j].poz]-=flow;
r[tata[j].poz^1]+=flow;
}
sol+=flow;
}
}
}
}
}
signed main ()
{
int m;
f >> n >> m;
for (int i=1; i<=m; i++)
{
int x, y, c;
f >> x >> y >> c;
v[x].push_back({y, cnt});
r[cnt]+=c;
cnt++;
v[y].push_back ({x, cnt});
cnt++;
}
s=1, d=n;
flux_maxim();
g << sol;
}