Problem:
Score: 300 points

Problem Statement

Find the minimum prime number greater than or equal to X.

Notes

A prime number is an integer greater than 1 that cannot be evenly divided by any positive integer except 1 and itself.

For example, 2, 3, and 5 are prime numbers, while 4 and 6 are not.

Constraints

2 \le X \le 10^5

All values in input are integers.

Input

Input is given from Standard Input in the following format:

X

Output

Print the minimum prime number greater than or equal to X.

Sample Input 1

20

Sample Output 1

23

The minimum prime number greater than or equal to 20 is 23.

Sample Input 2

2

Sample Output 2

2

X itself can be a prime number.

Sample Input 3

99992

Sample Output 3

100003

Solution in Java (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        // 整数の入力
        int x = sc.nextInt();
     	for(int i=x;i<x+100002;i++){
         if(isprime(i)){
            System.out.println(i);
           	break;
        }
    }
 }public static boolean isprime(int num){
      boolean isp = true;
      for(int i=2;i<=Math.sqrt(num)+1;i++){
        if (num%i == 0){
        isp = false;
        }
      }
      return isp;
    }
}