C Program to Check Whether a Number is Even or Odd

Howdy readers, today you will learn how to write a program to check whether a number is even or odd using C Programming language.

If any number is exactly divisible by 2, then it is an even number otherwise it’s an odd number.

You can also say any number modulo(%) divided by 2 equals to 0 is an even number. We will be using the Modulus(%) operator in our program to check whether a number is even or odd.

We will write this program using the following methods:

1. Using Modulus(%) operator
2. Using Bitwise operator
3. Using User-defined Function

So, without any delay, let’s begin this tutorial.

C Program to Check Whether a Number is Even or Odd

C Program

// C Program to Check Whether a Number is Even or Odd
#include <stdio.h>
int main(){
    int num;
    
    // Asking for input
    printf("Please enter a number: ");
    scanf("%d", &num);
    
    // Check even or odd
    if (num % 2 == 0){
        printf("%d is an even number.", num);
    }
    else {
        printf("%d is an odd number.", num);
    }
    
    return 0;
}

Output 1

Please enter a number: 7
7 is an odd number.

Output 2

Please enter a number: 68
68 is an even number.

Explanation

    int num;

In this program, we have declared an int data type variable named num.

    // Asking for input
    printf("Please enter a number: ");
    scanf("%d", &num);

Then, the user is asked to enter a number. This number gets stored in the num named variable.

    if (num % 2 == 0){
        printf("%d is an even number.", num);
    }
    else {
        printf("%d is an odd number.", num);
    }

Now, we check whether the entered number is divisible by 2 or not.

If the entered number is divisible by 2, then it is an even number otherwise it’s an odd number.

C Program to Check Whether a Number is Even or Odd Using Bitwise Operator

C Program

// C Program to Check Whether a Number is Even or Odd Using Bitwise Operator
#include <stdio.h>
int main(){
    int num;
    
    // Asking for input
    printf("Enter an integer: ");
    scanf("%d", &num);
    
    // Even or Odd
    if (num & 1){
        printf("%d is an odd number.", num);
    }
    else {
        printf("%d is an even number.", num);
    }
    
    return 0;
}

Output

Enter an integer: 15
15 is an odd number.

C Program to Check Whether a Number is Even or Odd Using Functions

C Program

// C Program to Check Whether a Number is Even or Odd Using Functions
#include <stdio.h>
int even_odd(int n){
    if (n % 2 == 0)
        printf("%d is an even number.", n);
    else
        printf("%d is an odd number.", n);
}

int main(){
    int num;
    
    // Asking for input
    printf("Enter a number: ");
    scanf("%d", &num);
    
    // Calling custom function
    even_odd(num);
    
    return 0;
}

Output

Enter a number: 47
47 is an odd number.

Explanation

int even_odd(int n){
    if (n % 2 == 0)
        printf("%d is an even number.", n);
    else
        printf("%d is an odd number.", n);
}

In this program, we have defined a custom function named even_odd which checks whether a number is odd or even.

    // Calling custom function
    even_odd(num);

Then, we called this custom function in the main function to display the result.

Conclusion

I hope after reading this post, you understand how to write a program to check whether a number is even or odd using C Programming language.

If you have any doubt regarding this program, then let us know in the comment section. We will be delighted to solve your query.

Also read:

• C Program to Check Prime Number
• C Program to Find Largest of Two Numbers
• C Program to Find Largest of Two Numbers Using Ternary Operator