1260A - Heating - CodeForces Solution

#include <bits/stdc++.h>
#define pb push_back
#define int long long int
using namespace std;

int mod = 1000000007;

int apowb(int b, int p)
{
  int res = 1;
  while (p)
  {
    if (p & 1)
    {
      res = (res * b) % mod;
    }

    p = p / 2;
    b = (b * b) % mod;
  }
  return res;
}

signed main()
{
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  // cin>>t;
  while (t--)
  {
    int n;
    cin >> n;
    int x, y;
    for (int k = 0; k < n; k++)
    {
      cin >> y >> x;
      if (x < y)
        cout << x << endl;
      else
      {
        int q = x / y;
        int rem = x % y;
        int left = y - rem;
        int res = 0;
        for (int i = 0; i < left; i++)
        {
          res += apowb(q, 2);
        }
        for (int i = 0; i < y - left; i++)
        {
          res += apowb(q + 1, 2);
        }
        cout << res << endl;
      }
    }
  }
  return (0);
}