Question

用java编写程序求n!

输入一个正整数repeat (0<repeat<10)，做repeat次下列运算：
读入1 个正整数 n(n<=50)，计算并输出n! 。
例：括号内是说明
输入
3 (repeat=2)
1
10
5
输出
1.0
3628800.0
120.0

import java.util.Scanner;
public class Test40002 {
public static void main(String[] args) {
int ri, repeat;
int i, n;
double fact;
Scanner in=new Scanner(System.in);
repeat=in.nextInt();
for(ri=1; ri<=repeat; ri++){
n=in.nextInt();
/*--------------------*/
System.out.println(fact);
}
}
}

Answer 1

import java.util.Scanner;
public class Text{
    public static void main(String args[]){
       System.out.println("请输入n");
       Scanner sc = new Scanner(System.in);
       int n= sc.nextInt();
       int t=1;
       int i=1;
       while(i<=n){
       t=i*t;
       i=i+1;
       }
       System.out.println("n!="+t);
       
       
    }
}

 //补充，JAVA文件保存时文件名必须和类名相同。

Answer 2

import java.util.Scanner;

public class Test40002 {
public static void main(String[] args) {
int ri, repeat;
int i, n;
double fact;
Scanner in = new Scanner(System.in);
repeat = in.nextInt();

for (ri = 1; ri <= repeat; ri++) {
n = in.nextInt();
/*--------------------*/

fact = 1;

for(i = 1; i <= n; i++){
fact = fact * i;
}

/**** add ends */
System.out.println(fact);
}
}
}