#include <iostream>
#include <iomanip>
#include <math.h>

using namespace std;
int main(){

    unsigned long long input;
    double array[4];
    int dem = 0;

    while (dem < 4 && cin >> input ){
            array[dem] = sqrt(input);
            dem++;
    }
    for ( int i = dem - 1; i >= 0; i--)

        cout << setprecision(4) << fixed << array[i] << endl;

}

there should not have a array that with 4 length, it may have 5 or 6 or 100...echo, there is no limit