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Logical OR (||) Operator in C

Last Updated : December 17, 2025

Logical operators work with the test conditions and return the result based on the condition's results, these can also be used to validate multiple conditions together.

In C programming language, there are three logical operators Logical AND (&&), Logical OR (||) and Logician NOT (!).

Logical OR (||) operator in C

Logical OR is denoted by double pipe characters (||), it is used to check the combinations of more than one conditions; it is a binary operator – which requires two operands.

If any of the operand's values is non-zero (true), Logical OR (||) operator returns 1 ("true"), it returns 0 ("false") if all operand's values are 0 (false).

Syntax of Logical OR operator:

    condition1 || condition2

Truth table of logical OR operator:

condition1 	condition2	condition1 || condition2
1		1		1
1		0		1
0		1		1
0		0		0

C examples of Logical OR (||) operator

Example 1: Take a number and apply some of the conditions and print the result of expression containing logical OR operator.

// C program to demonstrate example of 
// Logical OR (||) operator 

#include <stdio.h>

int main()
{
    int num =10;
    
    //printing result with OR (||) operator
    printf("%d\n",(num==10 || num>=5));
    printf("%d\n",(num>=5  || num<=50));
    printf("%d\n",(num!=10 || num>=5));
    printf("%d\n",(num>=20 || num!=10));
    
    return 0;
}

Output

1
1
1
0

Example 2: Input gender in single character and print full gender (Ex: if input is 'M' or 'm' – it should print "Male").

// Input gender in single character and print full gender
// (Ex: if input is 'M' or 'm' - it should print "Male").

#include <stdio.h>

int main()
{
    char gender;
    
    //input gender
    printf("Enter gender (m/M/f/F): ");
    scanf("%c", &gender);
    
    //check the condition and print gender
    if(gender=='m' || gender=='M')
        printf("Gender is Male");
    else if(gender=='f' || gender=='F')
        printf("Gender is Female");
    else
        printf("Unspecified gender");
        
    return 0;
}

Output

Enter gender (m/M/f/F): m
Gender is Male

Second run:
Enter gender (m/M/f/F): F
Gender is Female 

Third run:
Enter gender (m/M/f/F): x
Unspecified gender

Example 3: Input an integer number and check whether it is divisible by 9 or 7.

// Input an integer number and check whether 
// it is divisible by 9 or 7.

#include <stdio.h>

int main()
{
    int num;
    
    //input number
    printf("Enter an integer number: ");
    scanf("%d", &num);
    
    //check the condition
    if(num%9==0 || num%7==0)
        printf("%d is divisible by 9 or 7\n",num);
    else
        printf("%d is not divisible by 9 or 7\n",num);
        
    return 0;
}

Output

First run:
Enter an integer number: 27
27 is divisible by 9 or 7

Second run:
Enter an integer number: 49
49 is divisible by 9 or 7

Third run:
Enter an integer number: 25
25 is not divisible by 9 or 7

Logical OR (||) Operator in C Exercise

Select the correct option to complete each statement about the logical OR (||) operator in C.

1. The logical OR (||) operator returns true when: --Select-- At least one operand is true Both operands are true Both operands are false
2. What will be the result of the expression (5 < 3) || (10 > 8) in C? --Select-- 1 (true) 0 (false) Compilation error
3. Which statement correctly describes the behavior of the || operator in C? --Select-- It uses short-circuit evaluation It always evaluates both operands It performs bitwise OR

Check Answers