#include <stdio.h>
#include<math.h>
int main()
{
int d,D;
float pi=3.14,area,k;
printf("enter inner diameter of a washer in centimeter : ");
scanf("%d",& d);
printf("enter outer diameter of a washer in centimeter:");
scanf ("%d",& D);
printf("D and d are %d and %d respectively ",D,d);
k=(pow(D,2)-pow(d,2));
area=pi*k/4;
if (d > D){
printf ("check your measurements !!!");
}else{
printf ("the Area of a washer is %f squarecentimeters" ,area);
}
return 0;
}
try this
hope it helps