#include<iostream.h>
#include<conio.h>
#include<stdio.h>
#include<math.h>
int main ()
{
float x, y;
printf("\nx=  ");
scanf("%f", &x);
if (x<0 && x != -10)
{
    printf("\nX out of range: negatives are forbidden!");
}
if (x>4)
{
   do
   {
       x=x-4;
   }while (x>=4);
}   
if (x != -10)
{
    if (x<1)
    {
        y = sqrt(1 - pow(x-1, 2));
    }else{
          if (x>=1 && x<3)
          {
             y = 1 - sqrt(1 - pow(x-2, 2));
          }else{
             y = sqrt(1 - pow(x-3, 2));
          }
    }
}
printf("\ny= %.2f",y);
_getch();
return 0;
}