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: Time Limit Exceeded)

#include<stdio.h>

/*
int check(int n){
  int i;
  if(n<2)return 0;
  if(n==2)return 1;
  if(n%2==0)return 0;
  for(i=3;i<=n/i;i+=2)
    if(n%i==0)
      return 0;
  return 1;
}
*/

/*
int check(int n){
  int i;
  if(n<2)return 0;
  if(n<4)return 1;
  if(n%2==0 || n%3==0)return 0;
  for(i=5;i*i<=n;i+=6)
    if(n%i==0 || n%(i+2)==0)
      return 0;
  return 1;
}
*/

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

int main(){
  int i,n,ans=0,a;
  scanf("%d",&n);
  for(i=0;i<n;i++){
    scanf("%d",&a);
    ans+=check(a);
  }
  printf("%d\n",ans);
  return 0;
}