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#include <fstream>
#include <vector>
#include <queue>
using namespace std;
const int N = 1001;
const int M = 10000;
const int INF = 1 << 30;
struct muchie
{
int x, y, c, f;
};
int n, nr, nivel[N], poz[N];
vector <int> a[N];
queue <int> q;
muchie v[M];
void adauga_muchie(int x, int y, int c)
{
v[nr] = (muchie){x, y, c, 0};
a[x].push_back(nr++);
v[nr] = (muchie){y, x, 0, 0};//muchia de intoarcere
a[y].push_back(nr++);
}
void init_nivel()
{
for (int i = 2; i <= n; i++)
{
nivel[i] = -1;
}
}
void init_poz()
{
for (int i = 1; i <= n; i++)
{
poz[i] = 0;
}
}
bool bfs()
{
init_nivel();
q.push(1);
while (!q.empty())
{
int x = q.front();
q.pop();
for (auto i: a[x])
{
int y = v[i].y, c = v[i].c, f = v[i].f;
if (c == f) continue;
if (nivel[y] != -1) continue;
nivel[y] = 1 + nivel[x];
q.push(y);
}
}
return (nivel[n] != -1);
}
int dfs(int x, int valf)
{
if (x == n)
{
return valf;
}
while (poz[x] < (int)a[x].size())
{
int i = a[x][poz[x]];
int y = v[i].y;
int c = v[i].c;
int f = v[i].f;
if (nivel[y] != 1 + nivel[x] || f == c)
{
poz[x]++;
continue;
}
int f_curent = dfs(y, min(valf, c - f));
if (f_curent != 0)
{
v[i].f += f_curent;
v[i ^ 1].f -= f_curent;
poz[x]++;
return f_curent;
}
poz[x]++;
}
return 0;
}
int flux()
{
int f = 0;
while (bfs())
{
int f_curent;
init_poz();
while ((f_curent = dfs(1, INF)) != 0)
{
f += f_curent;
}
}
return f;
}
int main()
{
ifstream in("maxflow.in");
ofstream out("maxflow.out");
int m;
in >> n >> m;
for (int i = 0; i < m; i++)
{
int x, y, c;
in >> x >> y >> c;
adauga_muchie(x, y, c);
}
in.close();
out << flux();
out.close();
return 0;
}