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 (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
)

func readInt(sc *bufio.Scanner) int {
	sc.Scan()
	num, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return num
}

func isPrimeNumber(num int) bool {
	if num < 2 {
		return false
	}
	if num == 2 {
		return true
	}
	if num%2 == 0 {
		return false
	}

	sqrtNum := math.Sqrt(float64(num))
	max := int(math.Floor(sqrtNum))

	for i := 3; i <= max; i += 2 {
		if num%i == 0 {
			return false
		}
	}

	return true
}

func main() {
	var sc = bufio.NewScanner(os.Stdin)

	count := readInt(sc)

	primeCount := 0
	for i := 0; i < count; i++ {
		num := readInt(sc)
		if isPrimeNumber(num) {
			primeCount++
		}
	}

	fmt.Println(primeCount)
}