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/// Ford-Fulkerson algorithm with Capacity Scaling - Solutie de 70 de puncte, Complexitate: O(log(C) * m * m) C - Capacitatea maxima a unei muchii, m - Nr. de muchii
#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define pf push_front
#define MOD 1000000007
#define MAX 1005
using namespace std;
map < pair < int, int >, int > h;
vector < int > v[MAX];
int n, prag;
bool viz[MAX];
int dfs(int nod, int minn);
int main()
{
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
int m, i, x, y, z, maxx = 0, r = 0;
cin >> n >> m;
for(i = 1; i <= m; i++)
{
cin >> x >> y >> z;
v[x].pb(y), h[{x, y}] = z, maxx = max(maxx, z);
if(h[{y, x}] == 0) v[y].pb(x);
}
prag = (1<<int(log2(maxx)));
while(prag != 0)
{
for(i = 1; i <= n; i++) viz[i] = 0;
x = dfs(1, INT_MAX);
if(x != 0) r += x;
else prag /= 2;
}
cout << r;
return 0;
}
int dfs(int nod, int minn)
{
viz[nod] = 1;
if(nod == n) return minn;
for(int it:v[nod]) if(viz[it] == 0 && h[{nod, it}] >= prag)
{
int x = dfs(it, min(minn, h[{nod, it}]));
if(x > 0)
{
h[{nod, it}] -= x;
h[{it, nod}] += x;
return x;
}
}
return 0;
}