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#include <fstream>
#include <vector>
#include <queue>
#include <string.h>
#define INF 1000000000
#define S 0
#define D 61
#define nodesMax 63
#define pb push_back
#define mkp make_pair
using namespace std;
ifstream fin("traseu.in");
ofstream fout("traseu.out");
int n, m, Sol;
int gIn[nodesMax], gOut[nodesMax], viz[nodesMax], dist[nodesMax], C[nodesMax][nodesMax], Cost[nodesMax][nodesMax], TT[nodesMax];
vector<int> G[nodesMax], sNodes, dNodes;
queue<int> Q;
bool bellmanFord()
{
for(int i=1; i<nodesMax; i++)
dist[i]=INF;
Q.push(S);
while(!Q.empty())
{
int node=Q.front();
Q.pop();
viz[node]=0;
for(vector<int>::iterator it=G[node].begin(); it!=G[node].end(); it++)
{
int fiu=*it;
if(C[node][fiu]!=0 && dist[node]+Cost[node][fiu]<dist[fiu])
{
dist[fiu]=dist[node]+Cost[node][fiu];
TT[fiu]=node;
if(viz[fiu]==0)
{
viz[fiu]=1;
Q.push(fiu);
}
}
}
}
return (dist[D]!=INF);
}
int main()
{
int a, b, c;
fin>>n>>m;
for(int i=1; i<=m; i++)
{
fin>>a>>b;
fin>>Cost[a][b];
gOut[a]++, gIn[b]++;
Sol+=Cost[a][b];
}
for(int k=1; k<=n; k++)
for(int i=1; i<=n; i++)
for(int j=1; j<=n; j++)
if(Cost[i][k] && Cost[k][j] && (Cost[i][k]+Cost[k][j]<Cost[i][j] || (Cost[i][j]==0)) && i!=j)
Cost[i][j]=Cost[i][k]+Cost[k][j];
for(int i=1; i<=n; i++)
{
if(gOut[i]>gIn[i])
{
dNodes.pb(i);
G[i].pb(D);
C[i][D]=gOut[i]-gIn[i];
}
if(gOut[i]<gIn[i])
{
sNodes.pb(i);
G[S].pb(i);
C[S][i]=gIn[i]-gOut[i];
}
}
for(vector<int>::iterator it1=sNodes.begin(); it1!=sNodes.end(); it1++)
{
int node1=*it1;
for(vector<int>::iterator it2=dNodes.begin(); it2!=dNodes.end(); it2++)
{
int node2=*it2;
G[node1].pb(node2);
G[node2].pb(node1);
C[node1][node2]=INF;
Cost[node2][node1]=-Cost[node1][node2];
}
}
while(bellmanFord())
{
int flow=INF;
for(int aux=D; aux!=S; aux=TT[aux])
flow=min(flow, C[TT[aux]][aux]);
for(int aux=D; aux!=S; aux=TT[aux])
{
C[TT[aux]][aux]-=flow;
C[aux][TT[aux]]+=flow;
}
Sol+=flow*dist[D];
}
fout<<Sol;
}