Write a C++ Program to Perform Arithmetic Operations on Two Numbers

Performing arithmetic operations is one of the first programs every beginner learns in C++. It helps understand user input, conditional statements, and basic operators. In this tutorial by cslearning.org, we will learn how to write a simple and student-friendly C++ program to accept two integers and an arithmetic operator (+, -, *, /) from the user, perform the operation, and display the result.

This guide includes introduction, logic, simple C++ source code, sample output, and viva questions with answers.

1. Introduction of Arithmetic Operations

Arithmetic operations are basic mathematical operations such as:

• Addition (+)
• Subtraction (-)
• Multiplication (*)
• Division (/)

In C++, we can perform these operations on numbers using operators. The program will allow the user to choose the operation by entering the operator symbol.

Example:
If user enters 10, 5, and + → Result = 15
If user enters 12, 3, and / → Result = 4

2. Logic of the Program

To perform arithmetic operations on two numbers:

1. Start the program.
2. Declare variables to store two integers and the operator.
3. Take input of two numbers and the operator from the user.
4. Use conditional statements (if-else or switch) to check the operator.
5. Perform the corresponding arithmetic operation.
6. Display the result.

Example:
If user enters 8, 4, and *
8 * 4 = 32 → Display 32

3. C++ Source Code (Easy Student Friendly Code)

#include <iostream>
using namespace std;

int main()
{
    int num1, num2;
    char op;
    float result;

    cout << "Enter first number: ";
    cin >> num1;

    cout << "Enter second number: ";
    cin >> num2;

    cout << "Enter an operator (+, -, *, /): ";
    cin >> op;

    if(op == '+')
    {
        result = num1 + num2;
    }
    else if(op == '-')
    {
        result = num1 - num2;
    }
    else if(op == '*')
    {
        result = num1 * num2;
    }
    else if(op == '/')
    {
        if(num2 != 0)
            result = (float)num1 / num2;
        else
        {
            cout << "Error! Division by zero.";
            return 0;
        }
    }
    else
    {
        cout << "Invalid operator!";
        return 0;
    }

    cout << "Result: " << result;

    return 0;
}

Explanation:

• char op stores the operator entered by the user.
• if-else statements check which operation to perform.
• Typecasting (float) is used for division to get decimal results.
• Division by zero is handled to avoid runtime errors.

4. Sample Output

Example 1:

Enter first number: 10
Enter second number: 5
Enter an operator (+, -, *, /): +
Result: 15

Example 2:

Enter first number: 12
Enter second number: 4
Enter an operator (+, -, *, /): /
Result: 3

Example 3:

Enter first number: 7
Enter second number: 0
Enter an operator (+, -, *, /): /
Error! Division by zero.

5. Viva Questions with Answers

Q1: Which operators are used for arithmetic operations in C++?
Answer: +, -, *, / are used.

Q2: Why do we typecast to float for division?
Answer: To get decimal results instead of integer division.

Q3: Which conditional statement is used in this program?
Answer: if-else statements are used to check the operator.

Q4: How is division by zero handled?
Answer: The program checks if the second number is zero before performing division.

Q5: Can we also use a switch statement for this program?
Answer: Yes, switch can be used to check the operator and perform the operation.

This program helps beginners understand user input, conditional statements, arithmetic operations, and typecasting in C++. Practice more C++ programs on cslearning.org to strengthen your programming fundamentals.