#include <stdio.h>
#include <math.h>
void printperfectSquares(int upperLimit) {
    if(upperLimit < 0){
    printf("Invalid input\n");
    return; 
    int i = 1;
    while(i * 1 <= upperLimit){
        printf("%d", i * i);
        i++;
    }
    printf("\n");
}
int main()
  {
      int upperLimit;
      scanf("%d", &upperLimit);
      printperfectSquares(upperLimit);
      return 0;
  }

    
}