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>
#define N 10000

int isprime(int);

int main() {

  int i, n, hantei, count=0; /*count=?´???°?????° */
  int num[N];

  scanf("%d", &n);
  for(i=0; i<n; i++){
    scanf("%d", &num[i]);
  }

  for(i=0; i<n; i++){
    hantei = isprime(num[i]);
    if(hantei==0) count++;
  }

  printf("%d\n", count);

  return 0;
}

int isprime(int num)
{
  int i;

  if(num==2) return 0;

    if(num < 2 || num%2==0) return 1;

    i = 3;
    while(i<=sqrt(num)){
      if(num%i==0) return 1;
      i = i+2;
    }

    return 0;
}