Example: Simple C Calculator in C

// Simple C Calculator
#include <stdio.h>

int main() {
    // Step 1: Declare variables to store numbers, operator, and result
    char operator_char;
    double num1, num2, result;

    // Step 2: Prompt user for the first number
    printf("Enter first number: ");
    scanf("%lf", &num1);

    // Step 3: Prompt user for the operator
    printf("Enter an operator (+, -, *, /): ");
    scanf(" %c", &operator_char); // Note the space before %c to consume newline

    // Step 4: Prompt user for the second number
    printf("Enter second number: ");
    scanf("%lf", &num2);

    // Step 5: Use a switch statement to perform the calculation based on the operator
    switch (operator_char) {
        case '+':
            result = num1 + num2;
            printf("Result: %.2lf + %.2lf = %.2lf\n", num1, num2, result);
            break;
        case '-':
            result = num1 - num2;
            printf("Result: %.2lf - %.2lf = %.2lf\n", num1, num2, result);
            break;
        case '*':
            result = num1 * num2;
            printf("Result: %.2lf * %.2lf = %.2lf\n", num1, num2, result);
            break;
        case '/':
            // Handle division by zero
            if (num2 == 0) {
                printf("Error: Division by zero is not allowed.\n");
            } else {
                result = num1 / num2;
                printf("Result: %.2lf / %.2lf = %.2lf\n", num1, num2, result);
            }
            break;
        default:
            printf("Error: Invalid operator entered.\n");
            break;
    }

    return 0;
}