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#include <fstream>
#include <queue>
#include <vector>
using namespace std;
ifstream fin("traseu.in");
ofstream fout("traseu.out");
const int inf= 1<<30;
const int nmax= 61;
int n, m, s, d, sol= 0, sum= 0;
bool u[nmax+1];
int dist[nmax+1], p[nmax+1], in[nmax+1], out[nmax+1];
int c[nmax+1][nmax+1], cost[nmax+1][nmax+1], f[nmax+1][nmax+1];
queue <int> q;
vector <int> v[nmax+1];
bool bellmanford( ) {
for ( int i= 0; i<=n+1; ++i ) {
dist[i]= inf;
p[i]= u[i]= 0;
}
dist[s]= 0;
u[s]= 1;
for ( q.push(s); !q.empty(); q.pop() ) {
int x= q.front();
for ( vector <int>::iterator it= v[x].begin(); it!=v[x].end(); ++it ) {
if ( c[x][*it]>f[x][*it] && dist[x]+cost[x][*it]<dist[*it] ) {
dist[*it]= dist[x]+cost[x][*it];
p[*it]= x;
if ( u[*it]==0 ) {
u[*it]= 1;
q.push(*it);
}
}
}
u[x]= 0;
}
return dist[d]!=inf;
}
int fmcm( ) {
int ans= 0;
while ( bellmanford() ) {
int fmin= inf;
for ( int i= d; i!=s; i= p[i] ) {
fmin= min(fmin, c[p[i]][i]-f[p[i]][i]);
}
for ( int i= d; i!=s; i= p[i] ) {
f[p[i]][i]+= fmin;
f[i][p[i]]-= fmin;
}
ans= ans+fmin*dist[d];
}
return ans;
}
int main( ) {
fin>>n>>m;
s= 0, d= n+1;
for ( int cnt= 1, x, y, z; cnt<=m; ++cnt ) {
fin>>x>>y>>z;
v[x].push_back(y);
v[y].push_back(x);
++out[x];
++in[y];
c[x][y]= inf;
cost[x][y]= z;
cost[y][x]= -z;
sum+= z;
}
for ( int i= 1; i<=n; ++i ) {
if ( in[i]>out[i] ) {
v[s].push_back(i);
v[i].push_back(s);
c[s][i]= in[i]-out[i];
cost[s][i]= cost[i][s]= 0;
}
if ( in[i]<out[i] ) {
v[i].push_back(d);
v[d].push_back(i);
c[i][d]= out[i]-in[i];
cost[i][d]= cost[d][i]= 0;
}
}
sol= fmcm();
fout<<sol+sum<<"\n";
return 0;
}