Problem:
Prime Numbers

A prime number is a natural number which has exactly two distinct natural number divisors: 1 and itself. For example, the first four prime numbers are: 2, 3, 5 and 7.

Write a program which reads a list of N integers and prints the number of prime numbers in the list.

Input

The first line contains an integer N, the number of elements in the list.

N numbers are given in the following lines.

Output

Print the number of prime numbers in the given list.

Constraints

1 ≤ N ≤ 10000

2 ≤ an element of the list ≤ 108

Sample Input 1

5
2
3
4
5
6

Sample Output 1

3

Sample Input 2

11
7
8
9
10
11
12
13
14
15
16
17

Sample Output 2

4

Solution in C (judge verdict: Accepted)

#include <stdio.h>
#include <math.h>

int main(void){
    int a = 0, x, i = 0;
    int flag;
   while(scanf("%d",&x) != EOF) {
       flag = 1;
       if(x == 2) ;
       else if(x<2 || x%2 == 0) flag = 0;
       else {
            i = 3;
            while(i <= sqrt(x)) {
                if(x%i == 0) {
                    flag = 0;
                }
                i = i + 2;
            }
       }
       if(flag == 1) a++;
   }
   printf("%d\n",a);
   return 0;
}