Program to find out the area of circle by using macro

//Program to find out the area of circle by using macro
#include<stdio.h>
#include<conio.h>
#define pi 3.1416//macro
int main()
{
  float area, radius;
  clrscr();
  printf("Enter the radius of circle whose area to be calculated\n");
  scanf("%f",&radius);
  area=pi*radius*radius;
  printf("\nThe Area of the Circle is = %f",area);
 
  getch();
  return 0;
}

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