func_code_string: #include <bits/stdc++.h>   #pragma comment(linker,  /STACK:100000000 )   using namespace std;   int ri() {     int x;     scanf( %d , &x);     return x;   }   int cnt[1000100];   int main() {     int n, m;     scanf( %d %d , &n, &m);     long long ans = (long long)n * (long long)(n - 1) * (long long)(n - 2) / 6LL;     for (int i = 0; i < m; i++) {       int a, b;       scanf( %d %d , &a, &b);       cnt[a]++;       cnt[b]++;     }     long long sub = 0;     for (int i = 1; i <= n; i++) {       if (cnt[i] != 0) {         sub += (long long)cnt[i] * (n - 1 - (long long)cnt[i]);       }     }     ans -= sub / 2LL;     printf( %lld n , ans);     return 0;   }   