Java 实例 - 阶乘
一个正整数的阶乘(英语:factorial)是所有小于及等于该数的正整数的积,并且有0的阶乘为1。自然数n的阶乘写作n!。
亦即n!=1×2×3×...×n。阶乘亦可以递归方式定义:0!=1,n!=(n-1)!×n。
以下实例演示了 Java 阶乘代码的实现:
MainClass.java 文件
public class MainClass {
public static void main(String args[]) {
for (int counter = 0; counter <= 10; counter++){
System.out.printf("%d! = %d\n", counter,
factorial(counter));
}
}
public static long factorial(long number) {
if (number <= 1)
return 1;
else
return number * factorial(number - 1);
}
}
public class MainClass {
public static void main(String args[]) {
for (int counter = 0; counter <= 10; counter++){
System.out.printf("%d! = %d\n", counter,
factorial(counter));
}
}
public static long factorial(long number) {
if (number <= 1)
return 1;
else
return number * factorial(number - 1);
}
}
以上代码运行输出结果为:
0! = 1
1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
8! = 40320
9! = 362880
10! = 3628800