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 5.4.1) (judge verdict: Accepted)

#include <stdio.h>


int main()
{

    int prime,flag = 0;
    scanf("%d", &prime);
    while(flag != 1)
    {
        int count = 0;
        for(int i = 2; i<=prime/2; i++)
        {
            if(prime%i == 0)
                count++;
        }
        if(count == 0)
        {
            printf("%d", prime);
            flag = 1;
        }
        else
            prime++;




    }
    return 0;
}