# Python typing practice snippet # This snippet defines a simple function to calculate the factorial of a number # and then calls it for demonstration. def calculate_factorial(n: int) -> int: """ Calculates the factorial of a non-negative integer. Args: n: The non-negative integer. Returns: The factorial of n. """ if n < 0: raise ValueError("Factorial is not defined for negative numbers.") elif n == 0: return 1 else: result = 1 for i in range(1, n + 1): result *= i return result # --- Main execution --- if __name__ == "__main__": number = 5 try: fact = calculate_factorial(number) print(f"The factorial of {number} is: {fact}") except ValueError as e: print(f"Error: {e}") # Another example number_two = 7 try: fact_two = calculate_factorial(number_two) print(f"The factorial of {number_two} is: {fact_two}") except ValueError as e: print(f"Error: {e}") # This code demonstrates basic function definition, loops, # conditional statements, and error handling in Python. ```java // Java typing practice snippet // This Java program calculates the sum of the first N natural numbers. public class SumOfNaturalNumbers { /** * Calculates the sum of the first 'n' natural numbers. * * @param n The number of natural numbers to sum. * @return The sum of the first 'n' natural numbers. */ public static int calculateSum(int n) { if (n < 0) { throw new IllegalArgumentException("Input must be a non-negative number."); } int sum = 0; for (int i = 1; i <= n; i++) { sum += i; } return sum; } // Main method - entry point of the program public static void main(String[] args) { int limit1 = 10; try { int result1 = calculateSum(limit1); System.out.println("The sum of the first " + limit1 + " natural numbers is: " + result1); } catch (IllegalArgumentException e) { System.out.println("Error: " + e.getMessage()); } int limit2 = 25; try { int result2 = calculateSum(limit2); System.out.println("The sum of the first " + limit2 + " natural numbers is: " + result2); } catch (IllegalArgumentException e) { System.out.println("Error: " + e.getMessage()); } } } // This snippet covers basic class structure, methods, loops, // and exception handling in Java. ```javascript // JavaScript typing practice snippet // This script defines a function to reverse a given string // and then demonstrates its usage. /** * Reverses a given string. * @param {string} str The input string to reverse. * @returns {string} The reversed string. */ function reverseString(str) { if (typeof str !== 'string') { console.error("Input must be a string."); return ""; } return str.split('').reverse().join(''); } // --- Demonstration --- console.log("Original string: Hello World"); const reversed1 = reverseString("Hello World"); console.log("Reversed string: " + reversed1); // Expected: dlroW olleH console.log("\nOriginal string: JavaScript"); const reversed2 = reverseString("JavaScript"); console.log("Reversed string: " + reversed2); // Expected: tpircSavaJ console.log("\nTesting with non-string input:"); const reversed3 = reverseString(12345); // Should log an error console.log("Reversed string (invalid input): " + reversed3); // This JavaScript code showcases function definition, string manipulation, // and basic type checking for robustness. ```go // Go typing practice snippet // This Go program checks if a given number is prime. package main import "fmt" // isPrime checks if a number is prime. // A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself. func isPrime(num int) bool { if num <= 1 { return false // Numbers less than or equal to 1 are not prime } for i := 2; i*i <= num; i++ { if num%i == 0 { return false // Divisible by a number other than 1 and itself } } return true // No divisors found, so it's prime } func main() { // Test cases for isPrime function numbersToTest := []int{1, 2, 3, 4, 5, 7, 10, 11, 13, 17, 20, 23, 29} fmt.Println("Checking prime numbers:") for _, num := range numbersToTest { if isPrime(num) { fmt.Printf("%d is a prime number.\n", num) } else { fmt.Printf("%d is not a prime number.\n", num) } } } // This Go snippet demonstrates basic function definition, loops, // conditional statements, and array iteration. ```rust // Rust typing practice snippet // This Rust program calculates the nth Fibonacci number using an iterative approach. // Calculates the nth Fibonacci number. // The sequence starts with 0, 1, 1, 2, 3, 5... fn fibonacci(n: u32) -> u64 { if n == 0 { return 0; } else if n == 1 { return 1; } let mut a: u64 = 0; let mut b: u64 = 1; let mut sum: u64 = 0; // Iterate n-1 times to reach the nth Fibonacci number for _i in 2..=n { sum = a + b; a = b; b = sum; } b // 'b' will hold the nth Fibonacci number } fn main() { // Test cases for the fibonacci function let n1 = 0; println!("Fibonacci({}) is: {}", n1, fibonacci(n1)); // Expected: 0 let n2 = 1; println!("Fibonacci({}) is: {}", n2, fibonacci(n2)); // Expected: 1 let n3 = 5; println!("Fibonacci({}) is: {}", n3, fibonacci(n3)); // Expected: 5 (0, 1, 1, 2, 3, 5) let n4 = 10; println!("Fibonacci({}) is: {}", n4, fibonacci(n4)); // Expected: 55 let n5 = 20; println!("Fibonacci({}) is: {}", n5, fibonacci(n5)); // Expected: 6765 } // This Rust code demonstrates function definition, mutable variables, // loops, and basic ownership/borrowing concepts (implicitly here). ```cpp // C++ typing practice snippet // This C++ program implements a simple function to check if a number is even or odd. #include <iostream> // Required for input/output operations #include <string> // Required for using string class // Function to check if a number is even or odd // Returns "Even" if the number is even, "Odd" otherwise. std::string checkEvenOrOdd(int number) { if (number % 2 == 0) { return "Even"; } else { return "Odd"; } } int main() { // Test cases for the checkEvenOrOdd function int num1 = 4; std::cout << num1 << " is " << checkEvenOrOdd(num1) << std::endl; // Expected: 4 is Even int num2 = 7; std::cout << num2 << " is " << checkEvenOrOdd(num2) << std::endl; // Expected: 7 is Odd int num3 = 0; std::cout << num3 << " is " << checkEvenOrOdd(num3) << std::endl; // Expected: 0 is Even int num4 = -3; std::cout << num4 << " is " << checkEvenOrOdd(num4) << std::endl; // Expected: -3 is Odd // Return 0 to indicate successful execution return 0; } // This C++ snippet covers basic function definition, conditional statements, // input/output using iostream, and string manipulation.