Howdy readers, today you will learn **how to write a C program to find the remainder without using the modulo operator**.

In the C Programming language, the modulus operator **(%) **is used to find the remainder. For example, **15 % 4 => 3** where **3** is the remainder.

But in this program, we will find the remainder without the modulo operator. We will be using the following methods to find the remainder:

- Using Mathematics
- Using Repeated Subtraction

So, without any delay, letâ€™s begin this tutorial.

**C Program to Find the Remainder Without Using Modulo Operator**

**C Program**

// C Program to Find the Remainder Without Using Modulo Operator #include <stdio.h> int main(){ int a, b, rem; // Taking Input printf("Enter the first number: "); scanf("%d", &a); printf("Enter the second number: "); scanf("%d", &b); // Remainder rem = a - (a/b) * b; // Display Remainder printf("The remainder is: %d", rem); return 0; }

**Output**

Enter the first number: 20 Enter the second number: 3 The remainder is: 2

**Explanation**

int a, b, rem;

We have created three integer variables to store the values of dividend **(a)**, divisor **(b)** and the remainder **(rem)**.

printf("Enter the first number: "); scanf("%d", &a); printf("Enter the second number: "); scanf("%d", &b);

The user is asked to input the dividend and divisor. The dividend and divisor are stored in the **a** and **b** variables respectively.

rem = a - (a/b) * b;

Now, we used the mathematical formula to find the remainder.

**Dividend = (Quotient x Divisor) + Remainder**

It can also be written as,

Remainder = Dividend – (Quotient x Divisor)

rem = a – ((a/b) * b)

where,

- a is the dividend
- b is the divisor
- rem is the remainder

**Note:** a/b returns quotient.

The computed remainder is stored in the **rem** variable.

printf("The remainder is: %d", rem);

In the end, we print the value of the remainder on the screen using the **printf()** function.

**C Program to Find the Remainder Using Repeated Subtraction**

**C Program**

// C Program to Find the Remainder Using Repeated Subtraction #include <stdio.h> int main(){ int a, b, r; // Taking Input printf("Enter a dividend: "); scanf("%d", &a); printf("Enter a divisor: "); scanf("%d", &b); // Remainder Using Repeated Subtraction while (a > b){ a = a - b; } // Store Remainder Value r = a; // Print Remainder printf("The remainder is: %d", r); return 0; }

**Output**

Enter a dividend: 10 Enter a divisor: 3 The remainder is: 1

**Explanation**

while (a > b){ a = a - b; }

We used a while loop to find out the remainder.

Suppose the user enters **a = 10** and **b = 3**. Then,

**1st While Loop Iteration:**- while (10 > 3), the condition is True.
- a = a – b => 10 – 3 => 7.

**2nd While Loop Iteration:**- while (7 > 3), the condition is True.
- a = a – b => 7 – 3 => 4.

**3rd While Loop Iteration:**- while (4 > 3), the condition is True.
- a = a – b => 4 – 3 => 1

**4th While Loop Iteration:**- while (1 > 3), the condition is
**False**, so the loop terminates. The value of**a**becomes**1**.

- while (1 > 3), the condition is

r = a;

The leftover value is the remainder which is stored in the **r** variable.

**Conclusion**

Today you learned how to write a C program to find the remainder without using the modulo operator (%).

You also learned how to find the remainder using

- Using Simple Mathematics
- Using Repeated Subtraction

If you have any queries, comment them down in the comment section.