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 cls(int);

int main()
{
  int n;
  int p;
  int i;
  int num=0;
  scanf("%d",&n);
  for(i=0;i<n;i++)
    {
      scanf("%d",&p);
      if(cls(p))num++;
    }
  printf("%d\n",num);
    return 0;
}

int cls(int n)
{
  int num=(int)sqrt(n);
  int i;
  for(i=2;i<=num;i++)
    {
      if(n%i==0)return 0;
    }
  return 1;
}