2.40factorial.java

JAVA程序设计的源代码

public class Factorial{
public static void main(String []args){
System.out.println("Factorial of 3 is"+fact(3));
System.out.println("Factorial of 4 is"+fact(4));
System.out.println("Factorial of 5 is"+fact(5));
}

static int fact(int n) {
int result;
if(n==1)    //规定1!等于1
return 1;
result=fact(n-1)*n;    //结成运算规则n!=(n-1)!*n
return result;
}
}