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>
#define N 10000

int isprime(int);
int main(void) {
  int n, cnt;
  int i;
  int a[N];
  int b;
  cnt = 0;
  scanf("%d",&n);
 for(i=0;i<n;i++){
   scanf("%d",&a[i]);
 }
 
 for(i=0;i<n;i++){
   b = isprime(a[i]);
   if(b==1)cnt++;
 }

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

int isprime(int x){
  int i;
  
  if (x == 2){
    return 1;
  }

  else if(x < 2 || x % 2 == 0){
    return 0;
  }
 
  for(i=3;i*i<=x;i=i+2){
    if(x%i==0)return 0;
  }
  return 1;
  }