# C Program to Perform Arithmetic Operations Using Functions

In this program, we will learn how to perform arithmetic operations using functions in the C Programming language.

This program asks the user to enter two numbers. Then, it finds Addition, Subtraction, Multiplication, Division and Modulus of those two numbers using user-defined functions.

So, without further ado, let’s begin this tutorial.

Contents

## C Program to Perform Arithmetic Operations Using Functions

```// C Program to Perform Arithmetic Operations Using Functions
#include <stdio.h>

int sum = a + b;
return sum;
}

// Declaring subtraction function
int subtract(int a, int b){
int difference = a - b;
return difference;
}

// Declaring multiplication function
int multiply(int a, int b){
int multiply = a * b;
return multiply;
}

// Declaring division function
float division(float a, float b){
float divide = a / b;
return divide;
}

// Declaring modulus function
float mod(int a, int b){
int rem = a % b;
return rem;
}

int main(){
int num1, num2;

printf("Enter the first number: ");
scanf("%d", &num1);
printf("Enter the second number: ");
scanf("%d", &num2);

// Displaying output
printf("Arithmetic operations on %d and %d: \n", num1, num2);
printf("Subtraction: %d\n", subtract(num1, num2));
printf("Multiplication: %d\n", multiply(num1, num2));
printf("Division: %f\n", division(num1, num2));
printf("Modulus: %d\n", mod(num1, num2));
return 0;
}
```

Output

``````Enter the first number: 8
Enter the second number: 3
Arithmetic operations on 8 and 3:
Subtraction: 5
Multiplication: 24
Division: 2.666667
Modulus: 3
``````

## How Does This Program Work ?

```// Declaring addition function
int sum = a + b;
return sum;
}
```

In this program, we have defined a custom function named addition which returns the sum of two numbers.

```// Declaring subtraction function
int subtract(int a, int b){
int difference = a - b;
return difference;
```

Similarly, we defined a function named subtract which returns the difference of two numbers.

```// Declaring multiplication function
int multiply(int a, int b){
int multiply = a * b;
return multiply;
}
```

Now, we defined a custom function named multiply which returns the product of two numbers.

```// Declaring division function
float division(float a, float b){
float divide = a / b;
return divide;
}
```

We defined a custom function named division which performs division of two numbers.

```// Declaring modulus function
float mod(int a, int b){
int rem = a % b;
return rem;
}
```

At last, we defined a custom function named mod which returns the modulus of two numbers.

```    // Asking for input
printf("Enter the first number: ");
scanf("%d", &num1);
printf("Enter the second number: ");
scanf("%d", &num2);
```

Now, the user is asked to enter two numbers.

```    // Displaying output
printf("Arithmetic operations on %d and %d: \n", num1, num2);
printf("Subtraction: %d\n", subtract(num1, num2));
printf("Multiplication: %d\n", multiply(num1, num2));
printf("Division: %f\n", division(num1, num2));
printf("Modulus: %d\n", mod(num1, num2));
```

Finally, we call all the custom functions in the main function and display the result with the help of printf() function.

## Conclusion

I hope after going through this post, you understand how to perform arithmetic operations using functions in C Programming language.

If you have any doubt regarding the program, feel free to contact us in the comment section. We will be delighted to assist you.