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#include<fstream>
#include<bitset>
#include<queue>
#include<vector>
#include<algorithm>
using namespace std;
#define NMax 70
#define inf 2100000000
ifstream f("traseu.in");
ofstream g("traseu.out");
int n,m,S,D;
vector<int> v[NMax];
int ant[NMax];
int C[NMax][NMax],F[NMax][NMax];
int Cost[NMax][NMax];
queue<int> cd;
bitset<NMax> B;
int d[NMax];
void Bellmanford()
{
int i,s;
while(!cd.empty())
{
s=cd.front(); cd.pop();
B[s]=0;
for(i=0;i<(int)v[s].size();i++) if(F[s][v[s][i]]<C[s][v[s][i]]) if(d[v[s][i]]>d[s]+Cost[s][v[s][i]])
{
ant[v[s][i]]=s;
d[v[s][i]]=d[s]+Cost[s][v[s][i]];
if(!B[v[s][i]]) cd.push(v[s][i]),B[v[s][i]]=1;
}
}
}
int Flux()
{
for(int i=1;i<=n;i++) d[i]=inf,ant[i]=0;
d[S]=0;
cd.push(S);
Bellmanford();
if(d[D]==inf) return 0;
int fmin=inf;
int nod=D;
while(ant[nod])
{
fmin=min(fmin,C[ant[nod]][nod]-F[ant[nod]][nod]);
nod=ant[nod];
}
nod=D;
while(ant[nod])
{
F[ant[nod]][nod]+=fmin;
F[nod][ant[nod]]-=fmin;
nod=ant[nod];
}
return fmin*d[D];
}
int gr[NMax];
int main()
{
int i,a,b,c;
f>>n>>m;
S = n+1;
D = n+2;
int flux=0,cost=0;
for(i=1;i<=m;i++)
{
f>>a>>b>>c;
v[a].push_back(b);
v[b].push_back(a);
C[a][b]=inf;
Cost[a][b]=c;
Cost[b][a]=-c;
flux += c;
gr[a]--;
gr[b]++;
}
for(i=1;i<=n;++i) if(gr[i]>0)
{
v[S].push_back(i);
v[i].push_back(S);
C[S][i] = gr[i];
}
else if(gr[i]<0)
{
v[i].push_back(D);
v[D].push_back(i);
C[i][D] = -gr[i];
}
n += 2;
while(cost=Flux()) flux+=cost;
g<<flux<<"\n";
f.close();
g.close();
return 0;
}