#include <iostream>
#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#include<iomanip>
using namespace std;
void main(){
    std::cout<<fixed;
    cout.precision(4);
long double K[500];long double L[500]; int flag=0;

while (std::cin>>K[flag])
{flag++;
};






for(int k=flag-1;k>=0;k--){L[k]=sqrt((double)K[k]);
std::cout <<L[k]<<"\n";};
printf(" ");
//system("pause");
}

and I have this problem.. what this ?!!