exam6_1_2.java

来自「基本的数据结构的java代码」· Java 代码 · 共 35 行

public class Exam6_1_2{
	public static long fact(int n) throws Exception{
		int x;
		long y;
		
		if(n < 0){
			throw new Exception("参数错！");
		}
		
		if(n == 0){
			System.out.println("n="+n);
			return 1;
		}
		else{
			x = n - 1;
			System.out.println("n=" + n + " x=" + x);
			y = fact(x);
			System.out.println("n=" + n + " x=" + x + " y=" + y);
			return n * y;
		}
	}
	
	public static void main(String[] args){
		int n = 3;
		long fn;
		
		try{
			fn = fact(n);
			System.out.println("fn = " + fn);
		}
		catch(Exception e){
			System.out.println(e.getMessage());
		}
	}
}