Skip to content
Related Articles

Related Articles

Improve Article

Modulo Operator (%) in C/C++ with Examples

  • Difficulty Level : Easy
  • Last Updated : 06 May, 2021
Geek Week

The modulo operator, denoted by %, is an arithmetic operator.
The modulo division operator produces the remainder of an integer division. 

Syntax: If x and y are integers, then the expression: 

x % y

produces the remainder when x is divided by y. 

Return Value: 

  • If y completely divides x, the result of the expression is 0.
  • If x is not completely divisible by y, then the result will be the remainder in the range [1, x-1].
  • If x is 0, then division by zero is a compile-time error.

For example: Consider the following code:



C++




// Program to illustrate the
// working of modulo operator
#include <iostream>
using namespace std;
 
int main(void)
{
 
    // To store two integer values
    int x, y;
 
    // To store the result of
    // the modulo expression
    int result;
 
    x = 3;
    y = 4;
    result = x % y;
    cout << result << endl;
 
    result = y % x;
    cout << result << endl;
 
    x = 4;
    y = 2;
    result = x % y;
    cout<<result;
 
    return 0;
}
 
// This code is contributed by Mayank Tyagi

C




// Program to illustrate the
// working of modulo operator
 
#include <stdio.h>
 
int main(void)
{
 
    // To store two integer values
    int x, y;
 
    // To store the result of
    // the modulo expression
    int result;
 
    x = 3;
    y = 4;
    result = x % y;
    printf("%d", result);
 
    result = y % x;
    printf("\n%d", result);
 
    x = 4;
    y = 2;
    result = x % y;
    printf("\n%d", result);
 
    return 0;
}
Output
3
1
0

Restrictions of the modulo operator: 
The modulo operator has quite some restrictions or limitations.

  1. The % operator cannot be applied to floating-point numbers i.e float or double. If you try to use the modulo operator with floating-point constants or variables, the compiler will produce a error:

C++




// Program to illustrate the
// working of modulo operator
#include <iostream>
using namespace std;
 
int main()
{
     
    // To store two integer values
    float x, y;
 
    // To store the result of
    // the modulo expression
    float result;
 
    x = 2.3;
    y = 1.5;
    result = x % y;
    cout << result;
 
    return 0;
}
 
// This code is contributed by Harshit Srivastava

C




// Program to illustrate the
// working of modulo operator
 
#include <stdio.h>
 
int main(void)
{
 
    // To store two integer values
    float x, y;
 
    // To store the result of
    // the modulo expression
    float result;
 
    x = 2.3;
    y = 1.5;
    result = x % y;
    printf("%f", result);
 
    return 0;
}

Compilation Error: 

Compilation Error in C code :- prog.c: In function 'main':
prog.c:19:16: error:
 invalid operands to binary % (have 'float' and 'float')
     result = x % y;
                ^           

The sign of the result for modulo operator is machine-dependent for negative operands, as the action takes as a result of underflow or overflow. 

C++




// Program to illustrate the
// working of the modulo operator
#include <iostream>
using namespace std;
 
int main(void)
{
     
    // To store two integer values
    int x, y;
 
    // To store the result of
    // the modulo expression
    int result;
 
    x = -3;
    y = 4;
    result = x % y;
    cout << result << endl;
 
    x = 4;
    y = -2;
    result = x % y;
    cout << result << endl;
 
    x = -3;
    y = -4;
    result = x % y;
    cout << result;
 
    return 0;
}
 
// This code is contributed by Harshit Srivastava

C




// Program to illustrate the
// working of the modulo operator
 
#include <stdio.h>
 
int main(void)
{
 
    // To store two integer values
    int x, y;
 
    // To store the result of
    // the modulo expression
    int result;
 
    x = -3;
    y = 4;
    result = x % y;
    printf("%d", result);
 
    x = 4;
    y = -2;
    result = x % y;
    printf("\n%d", result);
 
    x = -3;
    y = -4;
    result = x % y;
    printf("\n%d", result);
 
    return 0;
}
Output
-3
0
-3

Note: Some compilers may show the result of the expression as 1 and other may show -1. It depends on the compiler.

Take a step-up from those “Hello World” programs. Learn to implement data structures like Heap, Stacks, Linked List and many more! Check out our Data Structures in C course to start learning today.



My Personal Notes arrow_drop_up
Recommended Articles
Page :