HDU ACMSteps 2.3.2 BigNumber

数学公式 log(10) n! = log 1 + log 2 + …… + log n 就能求出位数了，取下限

表示第一次用JAVA，勿喷~

import java.util.Scanner;


public class Main {
    public static void main(String[] args)
    {
        Scanner sc = new Scanner (System.in);
        int test;  test = sc.nextInt();
        int n;
        for(int rd = 0; rd != test; ++rd)
        {
            n = sc.nextInt();
            double res = 1;
            for(int i = 1; i <= n; ++i)
                res += Math.log10(i);
            int tmp = (int) Math.floor(res);
            
            System.out.println("" + tmp);
            
        }
        sc.close();
    }
}