Question

编写一个java循环程序从键盘输入一个数n求n！

Answer 1

import java.util.Scanner;

public class Test3 {

/**
* @param args
*/
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
System.out.println("请输入一个正整数n");
int num=in.nextInt();
int sum=1;
for(int i=1;i<=num;i++){
sum=sum*i;
}
System.out.println("sum="+sum);
}

}

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谢谢

Answer 2

public class test {

public static BigDecimal factorial(int n) {
BigDecimal result = new BigDecimal(1);
BigDecimal a;
for (int i = 2; i <= n; i++) {
a = new BigDecimal(i);
result = result.multiply(a);
}
return result;
}

public static void main(String[] arguments) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
System.out.println(a + "!=" + factorial(a));
}
}