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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
const int maxn = 1005;
int dist[maxn];
struct muchie {
int nod;
int vec;
int flux;
int cap;
};
vector <muchie> v[maxn];
muchie tata[maxn];
queue <int> q;
int n;
bool bfs()
{
for(int i = 1; i <= n; i++)
{
dist[i] = (1 << 30);
tata[i] = {0, 0, 0};
}
dist[1] = 0;
q.push(1);
while(!q.empty())
{
int nod = q.front();
q.pop();
for(auto it : v[nod])
{
if(dist[it.vec] > dist[nod] + 1 && it.flux < it.cap) /// pot trimite flux pe aici
{
dist[it.vec] = dist[nod] + 1;
tata[it.vec] = it;
q.push(it.vec);
}
}
}
if(dist[n] != (1 << 30))
return 1;
return 0;
}
vector <muchie> drum;
int main()
{
int m;
in >> n >> m;
for(int i = 1; i <= m; i++)
{
int x, y, cap;
in >> x >> y >> cap;
v[x].push_back({x, y, 0, cap});
v[y].push_back({y, x, 0, 0});
}
while(bfs()) /// cat timp gasesc un drum de la 1 la n
{
int act = n;
drum.clear();
while(tata[act].nod != 0)
{
drum.push_back(tata[act]);
act = tata[act].nod;
}
int posibil = (1 << 30); /// fluxul maxim pe care il pot trimite pe drumul gasit
for(auto it : drum) /// calculez ce flux pot trimite
posibil = min(posibil, it.cap - it.flux);
for(auto m : drum) /// scad si adun fluxul pe care il bag din toate muchiile
{
int x = m.nod;
int y = m.vec;
for(int i = 0; i < v[x].size(); i++) /// gasesc muchia (x, y) si adun fluxul bagat
{
if(v[x][i].vec == y)
{
v[x][i].flux += posibil;
break;
}
}
for(int i = 0; i < v[y].size(); i++)
{
if(v[y][i].vec == x)
{
v[y][i].flux -= posibil; /// gasesc muchia (y, x) si scad fluxul bagat
break;
}
}
}
}
int total = 0;
for(auto it : v[1]) /// ma uit cat iese din 1 ca sa aflu fluxul trimis
total = total + it.flux;
out << total << "\n";
return 0;
}