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 main(void){
    /*宣言部*/
    unsigned int input, answer=0, x, y, flag;    /*input:素数の全体数 answer:素数の総数 x, y:ループ変数 flag:フラグ*/
    long prime[10000], limit;    /*prime:素数 limit:素数調査のループ最大値*/
    
    /*入力部*/
    scanf("%u", &input);    /*全体数を読み取る*/
    for(x=0; input>x; x++){    /*素数をすべて読み取る*/
        scanf("%ld", &prime[x]);
    }
    
    /*計算部*/    /*2から判定対象未満までの数で、割り切れるかどうかで素数か判定する*/
    for(x=0; input>x; x++){
        limit=sqrt((float)prime[x]);
        for(y=2, flag=1; limit>=y; y++){    /*割り切れた時点でその数に対しての調査をやめる*/
            if(0==prime[x]%y){
                flag=0;
                break;
            }
        }
        if(1==flag){
            answer += 1;
        }
    }
    
    /*表示部*/
        printf("%u\n", answer);    /*素数の総数を表示する*/
    
    return 0;
}