#P990G. GCD Counting
GCD Counting
No submission language available for this problem.
Description
You are given a tree consisting of $n$ vertices. A number is written on each vertex; the number on vertex $i$ is equal to $a_i$.
Let's denote the function $g(x, y)$ as the greatest common divisor of the numbers written on the vertices belonging to the simple path from vertex $x$ to vertex $y$ (including these two vertices).
For every integer from $1$ to $2 \cdot 10^5$ you have to count the number of pairs $(x, y)$ $(1 \le x \le y \le n)$ such that $g(x, y)$ is equal to this number.
The first line contains one integer $n$ — the number of vertices $(1 \le n \le 2 \cdot 10^5)$.
The second line contains $n$ integers $a_1$, $a_2$, ..., $a_n$ $(1 \le a_i \le 2 \cdot 10^5)$ — the numbers written on vertices.
Then $n - 1$ lines follow, each containing two integers $x$ and $y$ $(1 \le x, y \le n, x \ne y)$ denoting an edge connecting vertex $x$ with vertex $y$. It is guaranteed that these edges form a tree.
For every integer $i$ from $1$ to $2 \cdot 10^5$ do the following: if there is no pair $(x, y)$ such that $x \le y$ and $g(x, y) = i$, don't output anything. Otherwise output two integers: $i$ and the number of aforementioned pairs. You have to consider the values of $i$ in ascending order.
See the examples for better understanding.
Input
The first line contains one integer $n$ — the number of vertices $(1 \le n \le 2 \cdot 10^5)$.
The second line contains $n$ integers $a_1$, $a_2$, ..., $a_n$ $(1 \le a_i \le 2 \cdot 10^5)$ — the numbers written on vertices.
Then $n - 1$ lines follow, each containing two integers $x$ and $y$ $(1 \le x, y \le n, x \ne y)$ denoting an edge connecting vertex $x$ with vertex $y$. It is guaranteed that these edges form a tree.
Output
For every integer $i$ from $1$ to $2 \cdot 10^5$ do the following: if there is no pair $(x, y)$ such that $x \le y$ and $g(x, y) = i$, don't output anything. Otherwise output two integers: $i$ and the number of aforementioned pairs. You have to consider the values of $i$ in ascending order.
See the examples for better understanding.
Samples
3
1 2 3
1 2
2 3
1 4
2 1
3 1
6
1 2 4 8 16 32
1 6
6 3
3 4
4 2
6 5
1 6
2 5
4 6
8 1
16 2
32 1
4
9 16 144 6
1 3
2 3
4 3
1 1
2 1
3 1
6 2
9 2
16 2
144 1