Preprocessor Directives in C

Program 1

// Program for Preprocessor diretive
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
#define SIZE 10
# define AND &&
# define OR ||
int main()
{
    system("cls");
    int a[SIZE],i;
    printf("Enter element in array");
    for(i=0;i<SIZE;i++)
    scanf("%d",&a[i]);
    for(i=0;i<SIZE;i++)
    printf(" %d ",a[i]);
    
    return 0;
}

Program 2

// Program for macro with argument
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
#define add(a,b) a+b
#define max(a,b) (a>b?a:b)
#define min(a,b) (a<b?a:b)
int main()
{
    int a,b,c;
    system("cls");
    printf("Enter two number");
    scanf("%d%d",&a,&b);
    // c=add(a,b);
    // printf("Addition is %d",c);
    c=max(a,b);
    printf("%d",c);
return 0;
}

Program 3

// Program for macro with argument
#include<stdio.h>
#include<conio.h>
#include<ctype.h>
#define area(r) 3.14*r*r
int main()
{
   float r,A;
   system("cls");
   printf("Enter redious");
   scanf("%f",&r);
   A=area(r);
   printf("Area is %.2f: ",A);
    
return 0;
}