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);

int main(void){

    int i, a, n, c=0, x;

    scanf("%d", &n);

    for(i=0; i<n; i++){
        scanf("%d", &x);
        if(isPrime(x) == 1) c++;
        else continue;
    }

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

    return 0;
}

int isPrime(int x){

    int i;

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

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

    return 1;
}