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 Go (judge verdict: Accepted)

package main
import (
	"fmt"
	"math"
)

type floats []float64
func (f floats)find(key float64)bool{
	for _, v := range f{
		if v==key{
			return true
		}
	}
	return false
}

func main(){
	var n int
	fmt.Scan(&n)
	cnt := 0
	// 既出の素数を保存しておく

	for i:=0; i<n; i++{
		var x float64
		var primes floats
		fmt.Scan(&x)
		if !primes.find(x) && check(x){
			cnt++
			primes = append(primes, x)
		}
	}
	fmt.Println(cnt)
}


func check(x float64)bool{
	for i:=2; i<int(math.Sqrt(x))+1; i++{
		if int(x)%i==0{
			return false
		}
	}
	return true
}