#include <iostream>
using namespace std;

int main() {
    char operation;
    double num1, num2, result;
    
    cout << "Enter first number: ";
    cin >> num1;
    
    cout << "Enter second number: ";
    cin >> num2;
    
    cout << "Enter operation (+, -, *, /): ";
    cin >> operation;
    
    switch(operation) {
        case '+':
            result = num1 + num2;
            break;
        case '-':
            result = num1 - num2;
            break;
        case '*':
            result = num1 * num2;
            break;
        case '/':
            if(num2 != 0) {
                result = num1 / num2;
            } else {
                cout << "Error: Division by zero!" << endl;
                return 1;
            }
            break;
        default:
            cout << "Error: Invalid operation!" << endl;
            return 1;
    }
    
    cout << "Result: " << result << endl;
    return 0;
}
    

1. What Is This C++ Calculator?

This C++ calculator demonstrates basic arithmetic operations using a switch statement for operation selection. It performs addition, subtraction, multiplication, and division with proper error handling for division by zero.

2. How The Calculator Works

The calculator follows this workflow:

1. Accepts two numerical inputs from the user
2. Prompts for an arithmetic operation (+, -, *, /)
3. Uses a switch statement to determine the operation to perform
4. Executes the appropriate calculation
5. Handles division by zero and invalid operation errors
6. Displays the result or error message

3. Understanding The Switch Statement

The switch statement is a control structure that evaluates an expression and matches it to various case labels. It provides a cleaner alternative to multiple if-else statements when dealing with multiple conditions based on the same variable.

Syntax:

switch(expression) {
    case value1:
        // code to execute
        break;
    case value2:
        // code to execute
        break;
    default:
        // code if no cases match
}
                    

4. Using The Calculator

Instructions: Enter two numbers, select an operation from the dropdown menu, and click "Calculate" to see the result. The calculator handles basic arithmetic operations with proper error checking.

5. Frequently Asked Questions (FAQ)

Q1: Why use a switch statement instead of if-else?
A: Switch statements are more efficient and readable when checking a single variable against multiple constant values.

Q2: What happens if I divide by zero?
A: The calculator includes error handling that detects division by zero and displays an appropriate error message.

Q3: Can I extend this calculator with more operations?
A: Yes, you can easily add more cases to the switch statement to support additional mathematical operations.

Q4: How does the break statement work in switch?
A: The break statement exits the switch block. Without it, execution would "fall through" to the next case.

Q5: What is the purpose of the default case?
A: The default case handles any input that doesn't match the specified cases, providing error handling for invalid operations.