P24098 [AtCoder] GCD or MIN
提高
题目描述

Problem Statement

There are $N integers A_1, A_2, A_3, \dots, A_N written on a$ blackboard.
You will do the following operation N - 1 times:

  • Choose two numbers written on the blackboard and erase them. Let x and y be the erased numbers. Then, write $\gcd(x, y)$ or $\min(x, y)$ on the blackboard.

After N - 1 operations, just one integer will remain on the blackboard. How many possible values of this number are there?

Input

Input is given from Standard Input in the following format:
N
$A_1 A_2 A_3 \dots A_N$

Output

Print the number of possible values of the last remaining number on the blackboard.

Constraints

  • $2 \le N \le 2000$
  • $1 \le A_i \le 10^9$
  • All values in input are integers.

Sample Input 1

3
6 9 12

Sample Output 1

2

The possible values of the last remaining number are 3 and 6.
We will have 3 in the end if, for example, we do as follows:

  • choose 9, 12 and erase them from the blackboard, then write $\gcd(9, 12) = 3$;
  • choose 6, 3 and erase them from the blackboard, then write $\min(6, 3) = 3$.

Also, we will have 6 in the end if, for example, we do as follows:

  • choose 6, 12 and erase them from the blackboard, then write $\gcd(6, 12) = 6$;
  • choose 6, 9 and erase them from the blackboard, then write $\min(6, 9) = 6$.

Sample Input 2

4
8 2 12 6

Sample Output 2

1

2 is the only number that can remain on the blackboard.

Sample Input 3

7
30 28 33 49 27 37 48

Sample Output 3

7

1, 2, 3, 4, 6, 7, and 27 can remain on the blackboard.

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
3 6 9 12
样例输出
2