func_code_string: #include <bits/stdc++.h>   using namespace std;   int m;   long long n;   long long deg[1001001], result;   vector<vector<int> > e;   int main() {     scanf( %d%d , &n, &m);     for (int i = 0; i < m; i++) {       int a, b;       scanf( %d%d , &a, &b);       deg[a]++;       deg[b]++;     }     result = 0;     for (int i = 1; i <= n; i++) result += (n - 1 - deg[i]) * deg[i];     result /= 2;     result = n * (n - 1) * (n - 2) / 6 - result;     cout << result;   }   