c program to check odd or even

C program to check odd or even using modulus operator

#include<stdio.h>
 
main()
{
   int n;
 
   printf("Enter an integer\n");
   scanf("%d",&n);
 
   if ( n%2 == 0 )
      printf("Even\n");
   else
      printf("Odd\n");
 
   return 0;
}

We can use bitwise AND (&) operator to check odd or even, as an example consider binary of 7 (0111) when we perform 7 & 1 the result will be one and you may observe that the least significant bit of every odd number is 1, so ( odd_number & 1 ) will be one always and also ( even_number & 1 ) is zero.

C program to check odd or even using bitwise operator

#include<stdio.h>
 
main()
{
   int n;
 
   printf("Enter an integer\n");
   scanf("%d",&n);
 
   if ( n & 1 == 1 )
      printf("Odd\n");
   else
      printf("Even\n");
 
   return 0;
}

Find odd or even using conditional operator

#include<stdio.h>
 
main()
{
   int n;
 
   printf("Input an integer\n");
   scanf("%d",&n);
 
   n%2 == 0 ? printf("Even\n") : printf("Odd\n");
 
   return 0;
}

C program to check odd or even without using bitwise or modulus operator

#include<stdio.h>
 
main()
{
   int n;
 
   printf("Enter an integer\n");
   scanf("%d",&n);
 
   if ( (n/2)*2 == n )
      printf("Even\n");
   else
      printf("Odd\n");
 
   return 0;
}

In c programming language when we divide two integers we get an integer result, For example the result of 7/3 will be 2.So we can take advantage of this and may use it to find whether the number is odd or even. Consider an integer n we can first divide by 2 and then multiply it by 2 if the result is the original number then the number is even otherwise the number is odd. For example 11/2 = 5, 5*2 = 10 ( which is not equal to eleven), now consider 12/2 = 6 and 6 *2 = 12 ( same as original number). These are some logic which may help you in finding if a number is odd or not.