题目描述
You are given an integer array $a$ of length $n$.
Does there exist an array $b$ consisting of $n+1$ positive integers such that $a_i=\gcd (b_i,b_{i+1})$ for all $i$ ($1 \leq i \leq n$)?
Note that $\gcd(x, y)$ denotes the greatest common divisor (GCD) of integers $x$ and $y$.
Input
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \leq t \leq 10^5$). Description of the test cases follows.
The first line of each test case contains an integer $n$ ($1 \leq n \leq 10^5$) — the length of the array $a$.
The second line of each test case contains $n$ space-separated integers $a_1,a_2,\ldots,a_n$ representing the array $a$ ($1 \leq a_i \leq 10^4$).
It is guaranteed that the sum of $n$ over all test cases does not exceed $10^5$.
Output
For each test case, output "YES" if such $b$ exists, otherwise output "NO". You can print each letter in any case (upper or lower).
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
样例输出
提示
In the first test case, we can take $b=[343,343]$.
In the second test case, one possibility for $b$ is $b=[12,8,6]$.
In the third test case, it can be proved that there does not exist any array $b$ that fulfills all the conditions.