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,num[N],cnt=0;
  scanf("%d",&n);
  for (i = 0; i < n; i++) {
  scanf("%d",&num[i]);
  }
  for (i = 0; i < n; i++) {
    if (isPrime(num[i]) == 1) cnt++;
  }
  printf("%d\n",cnt);
  return 0;
}

int isPrime(int n){
  int i;
  if (n == 2) return 1;
  if (n%2 == 0 || n < 2) return 0;
  for (i = 3; i <= sqrt(n); i+=2) {
    if (n%i == 0) return 0;
  }
  return 1;
}