[Offer收割]编程练习赛12 题目1 : 歌德巴赫猜想

 1 import java.util.Scanner;
 2 
 3 public class Main {
 4 
 5     public static boolean isPrim(int n) {
 6         for (int i = 2; i * i <= n; i++) {
 7             if (n % i == 0) {
 8                 return false;
 9             }
10         }
11         return true;
12     }
13 
14     public static void main(String[] args) {
15         Scanner sc = new Scanner(System.in);
16         int n = sc.nextInt();
17         for (int i = 2; i + i <= n; i++) {
18             if (isPrim(i) && isPrim(n - i)) {
19                 System.out.println(i + " " + (n - i));
20                 break;
21             }
22         }
23     }
24 }