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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.*;

class Main{
	public static void main(String[]args){
    	Scanner scan = new Scanner(System.in);
      	int x = scan.nextInt();
      	boolean found = false;
      	while(true){
          for(int i=x;;i++){
            int y=2;
            for(;y<Math.sqrt(i);y++){
            	if(i%y==0)break;
            }
            if(Math.sqrt(i)<y)
            found=true;
            if(found){
                  System.out.println(i);
              return;
            }  
          }
        
        }
    }
}