package com.koukay.test;
import java.util.ArrayList;
import java.util.List;
/**
* 质数大于1的自然数,并且只能被1和它本身整除
*/
public class T100_TestPrime {
public static void main(String[] args) {
List<Integer> prime = getPrime(0, 10);
prime.forEach(a-> System.out.println(a));
for (int i = 0; i < 10; i++) {
System.out.println(i+" "+isPrime(i));
}
}
/**
* 判断该数是不是质数
* @param num
* @return
*/
static boolean isPrime(int num){
if (num<2) return false;
for (int i = 2; i <= num/2 ; i++) {
if (num % i==0)return false;
}
return true;
}
/**
* 拿到一段区间的质数
* @param start
* @param end
* @return
*/
static List<Integer> getPrime(int start, int end){
if (start<2)start=2;
List<Integer> list= new ArrayList<>();
for (int i = start; i <=end ; i++) {
if (isPrime(i)) list.add(i);
}
return list;
}
}