Java 1000阶乘计算,阶乘计算所有公式

1000的阶乘使用BigInteger import java.math.BigInteger;import java.util.Scanner;public class Main {public static void main(String[] args) {Scanner sc = new Scanner(System.in);//获得nint num = sc.nextInt();//初始值int preanswer = 1;//转为字符串String s = String.valueOf(preanswer);//转为BigIntegerBigInteger answer = new BigInteger(s);//n的范围小于等于1000if (num <= 1000) {//循环求阶乘for (int i = 1; i <= num; i++) {//i转为字符串String valuei = String.valueOf(i);//i转为BigIntegerBigInteger value = new BigInteger(valuei);//同类型相乘answer = value.multiply(answer);}}System.out.println(answer);sc.close();}}