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 isprime(int num){
  int i;

  if(num == 2) return 1;

  if(num < 2 || num % 2 == 0) return 0;


    i = 3;
    while(i <= sqrt((double)num) ){
      if(num % i == 0) return 0;
      i = i + 2;
    }

    return 1;
}

int main(){
  int i,N,A[10000],c=0;

  scanf("%d", &N);
  for(i = 0 ; i < N ; i++){
    scanf("%d", &A[i]);
    c += isprime(A[i]);
  }

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