"""# ### 谜题描述 Dima the hamster enjoys nibbling different things: cages, sticks, bad problemsetters and even trees! Recently he found a binary search tree and instinctively nibbled all of its edges, hence messing up the vertices. Dima knows that if Andrew, who has been thoroughly assembling the tree for a long time, comes home and sees his creation demolished, he'll get extremely upset. To not let that happen, Dima has to recover the binary search tree. Luckily, he noticed that any two vertices connected by a direct edge had their greatest common divisor value exceed 1. Help Dima construct such a binary search tree or determine that it's impossible. The definition and properties of a binary search tree can be found [here.](https://en.wikipedia.org/wiki/Binary_search_tree) Input The first line contains the number of vertices n (2 ≤ n ≤ 700). The second line features n distinct integers a_i (2 ≤ a_i ≤ 10^9) — the values of vertices in ascending order. Output If it is possible to reassemble the binary search tree, such that the greatest common divisor of any two vertices connected by the edge is greater than 1, print \"Yes\" (quotes for clarity). Otherwise, print \"No\" (quotes for clarity). Examples Input 6 3 6 9 18 36 108 Output Yes Input 2 7 17 Output No Input 9 4 8 10 12 15 18 33 44 81 Output Yes Note The picture below illustrates one of the possible trees for the first example. The picture below illustrates one of the possible trees for the third example. Here is a reference code to solve this task. You can use this to help you genereate cases or validate the solution. ```python import sys range = xrange input = sys.stdin.readline n = int(input()) A = [int(x) for x in input().split()] good_gcd = [False]*(710**2) for i in range(n): for j in range(n): a,b = A[i],A[j] while b: a,b = b,a%b good_gcd[i+710*j]=a>1 good_gcd[i+710*n]=True good_gcd[n+710*i]=True mem = [-1]*(2*710**2) # [a,b) def can_bst(left,a,b): #assert(a 1 for j in range(n)] for i in range(n)] parent = [[-1]*n for _ in range(n)] dp = [[False]*n for _ in range(n)] # 构建根节点可能性 for i in range(n): dp[i][i] = True # 区间DP for l in range(2, n+1): for i in range(n - l + 1): j = i + l - 1 for k in range(i, j+1): left_ok = (k == i) or (dp[i][k-1] and gcd_cache[k][k-1]) right_ok = (k == j) or (dp[k+1][j] and gcd_cache[k][k+1]) if left_ok and right_ok: dp[i][j] = True parent[i][j] = k break return 'Yes' if dp[0][n-1] else 'No' @staticmethod def prompt_func(question_case): elements = ' '.join(map(str, question_case['array'])) return f"""Determine if a valid BST can be built from these sorted values where adjacent nodes have GCD>1. Input: {question_case['n']} {elements} Output format: [answer]Yes/No[/answer]""" @staticmethod def extract_output(output): matches = re.findall(r'\[answer\](Yes|No)\s*\[/answer\]', output, re.IGNORECASE) return matches[-1].capitalize() if matches else None @classmethod def _verify_correction(cls, solution, identity): return solution == identity['expected_answer']