#include<iostream>
using namespace std;

int main()
{
 // Declare length of square
 int length;

 // Get length of square
 cout << "Give length of side: ";
 cin >> length;

 // If square length is negative, insist user
 // enter length again
 while(length<0)
 {
   cout << "No! Enter positive side length: ";
   cin >> length;
 }

 // Report square area
 cout << "Area is " << length*length << endl;

 return 0;
}