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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
const int NSIZE = 60 + 10;
const int inf = 1 << 30;
int N , M , x , y , z , i , ci , fmin , flow , S , D;
int d[NSIZE] , flag[NSIZE] , nxt[NSIZE] , in[NSIZE] , out[NSIZE];
int p[NSIZE][NSIZE] , c[NSIZE][NSIZE] , f[NSIZE][NSIZE];
vector < int > g[NSIZE];
queue < int > inQ;
void add(int x,int y,int z,int cap)
{
g[x].push_back(y);
g[y].push_back(x);
c[x][y] += cap;
p[x][y] = z;
p[y][x] = -z;
}
bool bellman()
{
for (int i=1;i<=N;++i)
d[i] = inf;
d[S] = 0;
inQ.push(S);
flag[S] = 1;
while (!inQ.empty())
{
int crt = inQ.front();
inQ.pop() , flag[crt] = 0;
for (int i = 0;i < g[crt].size();++i)
{
int to = g[crt][i];
if (f[crt][to] < c[crt][to] && d[to] > d[crt] + p[crt][to])
{
d[to] = d[crt] + p[crt][to];
nxt[to] = crt;
if (flag[to] == 0)
{
inQ.push(to);
flag[to] = 1;
}
}
}
}
if (d[D] == inf) return false;
return true;
}
int main()
{
ifstream fin("traseu.in");
ofstream fout("traseu.out");
fin >> N >> M;
S = 0 , D = N + 1;
for (i=1;i<=M;++i)
{
fin >> x >> y >> z;
flow += z;
in[y] += 1 , out[x] += 1;
add(x , y , z , inf);
}
for (i=1;i<=N;++i)
(in[i] > out[i]) ? add(S , i , 0 , in[i] - out[i]) : add(i , D , 0 , out[i] - in[i]);
N += 1;
while (bellman())
{
fmin = inf;
for (i = D ; i != S ; i = nxt[i])
{
int to = nxt[i];
fmin = min(fmin , c[to][i] - f[to][i]);
}
flow += fmin * d[D];
for (i = D ; i != S ; i = nxt[i])
{
int to = nxt[i];
f[to][i] += fmin;
f[i][to] -= fmin;
}
}
fout << flow << '\n';
return 0;
}