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 <string.h>

#define MAX_N 10000

int is_prim(int val) {
  int i;
  if(val == 2) return 1;
  if(val < 2 || val%2 == 0) return 0;
  for(i = 3; i*i <= val; i+=2) {
    if(val%i == 0) return 0;
  }
  return 1;
}

int main() {
  int prim[MAX_N + 10];
  int n, val, ans = 0;
  int i;
  scanf("%d", &n);
  for(i = 0; i < n; i++) {
    scanf("%d", &val);
    if(is_prim(val)) ans++;
  }
  printf("%d\n", ans);
  return 0;
}