Basic Calculator in C++

This program creates a basic calculator that performs arithmetic operations (addition, subtraction, multiplication, division) on two numbers. It demonstrates the switch statement, which is perfect for handling multiple cases based on a single value. The program also includes error handling for division by zero and invalid operators.

What This Program Does

The program:

• Takes an arithmetic operator (+, -, *, /) as input
• Takes two numbers as input
• Performs the corresponding arithmetic operation
• Displays the result
• Handles errors (division by zero, invalid operator)

This is a fundamental program that teaches:

• Switch statement for multiple conditions
• Character input handling
• Error handling and validation
• Basic arithmetic operations

Understanding the Switch Statement

switch(op)

The switch statement is perfect for handling multiple cases based on a single value.

Syntax:

cpp
switch (variable) {
    case value1:
        // code for value1
        break;
    case value2:
        // code for value2
        break;
    default:
        // code if no case matches
}

Why use switch instead of if-else?

• Cleaner and more readable for multiple conditions
• More efficient (compiler can optimize)
• Easier to add new operations

Error Handling

Division by Zero:

• Check if num2 != 0 before dividing
• Print error message and exit if divisor is zero

Invalid Operator:

• Use default case to handle invalid operators
• Print error message and exit

Summary

• Switch statement handles multiple cases based on operator
• Each case performs corresponding arithmetic operation
• break; prevents falling through to next case
• Error handling for division by zero and invalid operators
• double type allows decimal number calculations
• return 1; indicates error, return 0; indicates success

This program teaches:

• Switch statement for multiple conditions
• Character input handling
• Error handling and validation
• Arithmetic operations in programming
• Program exit codes