User-Defined Functions

Write a program power that computes x raised to the power y fot integers x and y and returns double-typ value.

#include <stdio.h>
void main( )
{ int x,y;    /*input data */
 double power(int, int); /* prototype declaration*/
 printf("Enter x,y:");
 scanf("%d %d" , &x,&y);
 printf("%d to power %d is %f\n", x,y,power (x,y));
 getch();
}
double power (int x, int y)
{
 double p;
 p = 1.0 ;     /* x to power zero */
 if(y >=0)
  while(y--)   /* computes positive powers */
   p *= x;
 else
  while (y++)  /* computes negative powers */
   p /= x;
  return(p);   /* returns double type */
}

OUTPUT
Enter x,y : 16 2
16 to power 2 is 256.000000

Enter x,y : 16 -2
16 to power -2 is 0.003906