quirksome-squares.cpp

#include <bits/stdc++.h>

using namespace std;
int main(){
    int n;
    while(scanf("%d", &n) == 1) {
        for(int i = 0; i*i < pow(10, n); i++){
            if(pow(i*i % (int) pow(10, n / 2) + i*i / (int) pow(10, n / 2), 2) == i*i){
                printf("%0*d\n", n, i*i);
            }
        }
    }
    return 0;
}