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 n, count = 0, i, s, key;
   long a;
   scanf("%d", &n);
   for ( i = 0;  i < n; i++ ) {
      s = key = 2;
      scanf("%ld", &a);
      if ( a == 1 ) a;
      else if ( a == 2 ) {/*printf("sosuu\n")*/;count++;}
      else {
         while ( s < sqrt(a) + 2 && key != 0) {
            if ( a % s == 0 ) key = 0;
            else key = 1;
            s++;
         }
      }
      if ( a != 1 && s > sqrt(a) + 1) {/*printf("sosuu\n")*/;count++;}
   }
   printf("%d\n", count);
   return 0;
}