求出100~200之间的素数

求出100~200之间的素数的个数，并求出所有的素数。
分析：素数定义是只能被1和该数本身整除

package com.math.forth;/*** 求出100~200之间的素数的个数，并求出所有的素数。 * 分析：素数定义是只能被1和该数本身整除* * @author wql**/
public class Math02 {public static void main(String[] args) {int sum1 = method();System.out.println("\n一共有" + sum1 + "个素数");System.out.println("------------method2---------------");int sum2 = 0;for (int i = 100; i <= 200; i++) {if (method2(i)) {sum2++;System.out.print(i + " ");}}System.out.println("\n一共有" + sum2 + "个素数");System.out.println("------------method3---------------");int sum3 = 0;for (int i = 100; i <= 200; i++) {if (method3(i)) {sum3++;System.out.print(i + " ");}}System.out.println("\n一共有" + sum3 + "个素数");}public static int method() {int sum = 0;for (int i = 100; i <= 200; i++) {for (int j = 2; j < i; j++) {if (i % j == 0) {break;}if (j == i - 1) {System.out.print(i + " ");sum++;}}}return sum;}public static boolean method2(int i) {for (int j = 2; j < i; j++) {if (i % j == 0) {return false;}}return true;}/**
*数量级灰常大，运算能力强
*/public static boolean method3(long n) {for (long i = 2; i * i <= n; ++i) {if (n % i == 0) {return false;}}return true;}
}

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