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 C (GCC 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
int main ()
{
    int x,i,j,flag;
    scanf("%d", &x);
    for(i=x; i<x+100; i++){
        flag=0;
        for(j=2; j<=i/2; j++){
            if(i%j==0)
            {flag=1;
             break;}
    }
    if(flag==0){break;}
    }
    printf("%d", i);}