#include <stdio.h>
int main (){
  int i, n;
  scanf("%d", &n);
  
  int a, multi;
  for(i=0; i<n; ++i){
    scanf("%d", &a);
    multi = a * a;
    if(multi < 1000000000000000000){
      printf("%d", multi);
    }else{
      printf("%d", -1);
    }
   }
  return 0;
}
  