题解 | #判断质数# 最快速？

import java.util.Scanner;
import java.util.ArrayList;
import java.util.Collections;

public class Main {
    public static void main(String[] args) {
        Main main = new Main();
        Scanner scan = new Scanner(System.in);
        int number = scan.nextInt();
        System.out.println(main.isPrimeNumber(number));
    }

    public Boolean isPrimeNumber(int number) {

        //write your code here......
        if (number <= 1) return false;
        if (number < 6 && number != 4) return true;

        Integer[] intarr = {0, 2, 3, 4};
        ArrayList<Integer> arr = new ArrayList<Integer>(4);
        Collections.addAll(arr, intarr);
        if (arr.contains(number % 6)) return false;

        for (int i = 2; i <= (int)Math.pow(number, 0.5); i++) {
            if (number % i == 0) return false;
        }

        return true;


    }
}