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#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
#include <climits>
#define pii pair <int, int>
using namespace std;
ifstream fin("traseu.in");
ofstream fout("traseu.out");
const int N = 350, inf = INT_MAX;
int dist[N + 1], cdist[N + 1], from[N + 1], aux[N + 1], in[N + 1], out[N + 1];
int f[N + 1][N + 1], cost[N + 1][N + 1];
int n, m, S, D, maxFlow = 0, minCost = 0;
bool inQ[N + 1];
vector <int> adj[N + 1];
void BF(){
for(int i = 0; i <= n + 1; i++)
aux[i] = inf;
queue <int> Q;
Q.push(S), aux[S] = 0;
while(!Q.empty()){
int nod = Q.front();
Q.pop();
inQ[nod] = false;
for(auto vec : adj[nod])
if(aux[nod] + cost[nod][vec] < aux[vec] && f[nod][vec] > 0){
aux[vec] = aux[nod] + cost[nod][vec];
if(!inQ[vec])
Q.push(vec), inQ[vec] = true;
}
}
}
priority_queue <pii, vector <pii>, greater <pii>> pq;
bool DJK(){
for(int i = 0; i <= n + 1; i++)
dist[i] = cdist[i] = inf;
pq.push({0, S});
dist[S] = cdist[S] = 0;
while(!pq.empty()){
int nod = pq.top().second, val = pq.top().first;
pq.pop();
if(val == dist[nod])
for(auto vec : adj[nod])
if(f[nod][vec] > 0 && dist[nod] + cost[nod][vec] + aux[nod] - aux[vec] < dist[vec]){
dist[vec] = dist[nod] + cost[nod][vec] + aux[nod] - aux[vec];
cdist[vec] = cdist[nod] + cost[nod][vec];
pq.push({dist[vec], vec}), from[vec] = nod;
}
}
return(dist[D] != inf);
}
signed main(){
fin >> n >> m;
S = 0, D = n + 1;
int ans = 0;
for(int i = 1; i <= m; i++){
int a, b, z;
fin >> a >> b >> z;
adj[a].push_back(b);
adj[b].push_back(a);
in[b]++, out[a]++;
f[a][b] = inf, cost[a][b] = z, cost[b][a] -= z;
ans += z;
}
for(int i = 1; i <= n; i++){
if(in[i] > out[i]){
adj[S].push_back(i);
f[S][i] = in[i] - out[i];
}else if(in[i] < out[i]){
adj[i].push_back(D);
f[i][D] = out[i] - in[i];
}
}
BF();
while(DJK()){
int nod = D, flow = inf;
while(nod != S)
flow = min(flow, f[from[nod]][nod]), nod = from[nod];
nod = D, maxFlow += flow;
while(nod != S)
f[from[nod]][nod] -= flow, f[nod][from[nod]] += flow, nod = from[nod];
minCost += flow * cdist[D];
for(int i = 1; i <= n; i++)
aux[i] = dist[i];
}
fout << ans + minCost << '\n';
return 0;
}