func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long INF = 0x3f3f3f3f;   const long long MAXN = 3e5 + 5;   long long n, MOD, k, ans;   map<long long, long long> mp;   signed main() {     scanf( %lld%lld%lld , &n, &MOD, &k);     for (long long i = 1; i <= n; i++) {       long long x;       scanf( %lld , &x);       x = (x * x % MOD * x % MOD * x % MOD + MOD - x * k % MOD) % MOD;       mp[x]++;     }     for (map<long long, long long>::iterator it = mp.begin(); it != mp.end();          it++) {       long long x = it->second;       ans += (x - 1) * x / 2;     }     printf( %lld n , ans);     return 0;   }   