usaco-practice/cses/Number Spiral/index.cpp

#include <iostream>
using namespace std;

int main() {
  long long n;
  cin >> n;
  long long y, x;
  long long v;
  for (long long i = 0; i < n; i++) {
    cin >> y;
    cin >> x;

    if (y > x) {
      if (y % 2 == 0) {
        v = y * y;
        v -= x - 1;
      } else {
        v = (y - 1) * (y - 1) + 1;
        v += x - 1;
      }
    } else {
      if (x % 2 == 0) {
        v = (x - 1) * (x - 1) + 1;
        v += y - 1;
      } else {
        v = x * x;
        v -= y - 1;
      }
    }
    cout << v << endl;
  }
}