func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m;     cin >> n >> m;     vector<long long> f(n);     int u, v;     long long z;     while (m--) {       cin >> u >> v >> z;       f[--u] -= z;       f[--v] += z;     }     vector<long long> a, b;     for (int i = 0; i < n; i++)       if (f[i] > 0)         a.push_back(i);       else if (f[i] < 0)         b.push_back(i);     vector<vector<long long> > ans;     int id = 0;     for (int i = 0; i < a.size(); i++) {       while (id < b.size() && f[a[i]] > 0) {         long long x = min(f[a[i]], -f[b[id]]);         f[a[i]] -= x;         f[b[id]] += x;         ans.push_back({b[id], a[i], x});         if (f[b[id]] == 0) id++;       }     }     cout << ans.size() <<   n ;     for (auto x : ans) cout << x[0] + 1 <<     << x[1] + 1 <<     << x[2] <<   n ;   }   