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#include <fstream>
#include <queue>
#include <vector>
#include <cstring>
#include <algorithm>
using namespace std;
ifstream fin("traseu.in");
ofstream fout("traseu.out");
const int INF = 0x3f3f3f3f;
int N, M, S, D;
int sol;
int grdint[62], grdext[62];
int C[62][62], F[62][62], TT[62], Dmin[62];
vector<pair<int, int> > V[62];
queue<int> Q;
bool inQ[62];
bool bellman()
{
memset(inQ, false, sizeof(inQ));
memset(Dmin, INF, sizeof(Dmin));
Dmin[S] = 0;
Q.push(S);
inQ[S] = true;
while (!Q.empty())
{
int now = Q.front();
Q.pop();
inQ[now] = false;
if (now == D)
continue;
for (vector<pair<int, int> >::iterator it = V[now].begin(); it != V[now].end(); ++it)
{
if (F[now][it->first] < C[now][it->first])
{
if (Dmin[now] + it->second < Dmin[it->first])
{
Dmin[it->first] = Dmin[now] + it->second;
TT[it->first] = now;
if (!inQ[it->first])
{
Q.push(it->first);
inQ[it->first] = true;
}
}
}
}
}
return (Dmin[D] != INF);
}
int main()
{
fin >> N >> M;
S = 0;
D = N + 1;
for (int i = 1, nod1, nod2, lg; i <= M; ++i)
{
fin >> nod1 >> nod2 >> lg;
V[nod1].push_back(make_pair(nod2, lg));
V[nod2].push_back(make_pair(nod1, -lg));
C[nod1][nod2] = INF;
++grdext[nod1];
++grdint[nod2];
sol += lg;
}
for (int i = 1; i <= N; ++i)
{
if (grdext[i] < grdint[i])
{
C[S][i] = grdint[i] - grdext[i];
V[S].push_back(make_pair(i, 0));
V[i].push_back(make_pair(S, 0));
}
else if (grdext[i] > grdint[i])
{
C[i][D] = grdext[i] - grdint[i];
V[D].push_back(make_pair(i, 0));
V[i].push_back(make_pair(D, 0));
}
}
int fmin = INF;
while (bellman())
{
fmin = INF;
for (int nod = D; nod != S; nod = TT[nod])
fmin = min(fmin, C[TT[nod]][nod] - F[TT[nod]][nod]);
if (fmin == 0)
continue;
for (int nod = D; nod != S; nod = TT[nod])
{
F[TT[nod]][nod] += fmin;
F[nod][TT[nod]] -= fmin;
}
sol += fmin * Dmin[D];
}
fout << sol << '\n';
fin.close();
fout.close();
return 0;
}