Program to show nesting of macros

#include<stdio.h>

#define SQU(x)((x)*x)

#define CUBE(x)(SQU(x)*x)

int main()

{         

          int x,y;

          clrscr();

          x=SQU(3);

          y=CUBE(3);

          printf("\nSquare of 3 : %d",x);

          printf("\nCube of 3 : %d",y);

          return(0);

}