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: Runtime Error)

#include<stdio.h>
#define N 1000

int main(void){
  int a[N],  n, k, ans, w, j, an;
   scanf("%d", &n);
  for(k=0; k < n; k++) scanf("%d", &a[k]); 

  for(k=0; k < n; k++){

    for(j=1; j <= a[k]; j++) {
      an = a[k] % j;
      if(an == 0) w++;
      if(w == 2 && j != a[k]) break;
      else if(w == 2) ans++;
    }

    w=0;
  }

  printf("%d\n", ans);
  return 0;
}