递归实现阶乘：Python、Java 与 JavaScript 代码对比

Python 代码示例

python
def calculate_factorial(n):
    if n == 0 or n == 1:
        return 1
    else:
        return n * calculate_factorial(n - 1)

number = int(input("Enter a number: "))
print(f"The factorial of {number} is {calculate_factorial(number)}")

Java 代码示例

java
import java.util.Scanner;

public class Factorial {
    public static int calculateFactorial(int n) {
        if (n == 0 || n == 1) {
            return 1;
        } else {
            return n * calculateFactorial(n - 1);
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int number = scanner.nextInt();
        System.out.println("The factorial of " + number + " is " + calculateFactorial(number));
    }
}

JavaScript 代码示例

javascript
function calculateFactorial(n) {
    if (n === 0 || n === 1) {
        return 1;
    } else {
        return n * calculateFactorial(n - 1);
    }
}

const number = parseInt(prompt("Enter a number: "));
console.log(`The factorial of ${number} is ${calculateFactorial(number)}`);

代码说明

以上代码实现了计算一个数的阶乘的功能。用户输入一个数字，程序会计算并返回该数字的阶乘。递归方法被用来实现阶乘的计算。每种编程语言的实现方式略有不同，但核心逻辑相同。