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 TRUE 1
#define FALSE 0

int isPrime( int );
int main()
{
  int i, n, c = 0;
  int E[10000];
  
  scanf("%d", &n);
  for(i = 0; i < n; i++)
    {
      scanf("%d", &E[i]);
      if(isPrime( E[i] ) == TRUE) c++;
    }
  printf("%d\n", c);
  return 0;
}

int isPrime( int x )
{
  int i;
  
  if(x == 2) return TRUE;
  else if(x < 2 || x%2 == 0) return FALSE;
  else
    {
      i = 3;
      while( i <= sqrt(x) )
	{
	  if(x%i == 0) return FALSE;
	  i+=2;
	}
      return TRUE;
    }
}