题目描述
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.
Constraints
1 ≤ N ≤ 10000
2 ≤ an element of the list ≤ 108
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.
Examples
Input
5
2
3
4
5
6
Output
3
Input
11
7
8
9
10
11
12
13
14
15
16
17
Output
4
输入格式
见题面
输出格式
见题面
样例输入
5
2
3
4
5
6
样例输出
3