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 a(int x){
    int i;
    int y = (int)(sqrt(x)) + 1;

    for(i = 2; i < y;i++){
        if(x % i == 0){
            return 0;
        }
    }
    return 1;
}

int main(void){
    int n, i, x;
    int count = 0;
    int A[10000];
    scanf("%d", &n);
    for(i = 0; i < n; i++){
        scanf("%d\n", &A[i]);
        x = a(A[i]);
        if(x == 1){
            count++;
        }
    }
    printf("%d\n", count);

    return 0;
}