def longestCommonPrefix(strs): """  :param strs:list()  :return: len  """  res = ''  idx = 0  for i in zip(*strs): if idx == 0 and len(set(i)) != 1: return 0  # 如果第一个没一样，则return  idx += 1  if len(set(i)) == 1:
            res += i[0] return len(res)
n = int(input())
strs = []
nums = [] for i in range(n):
    strs.append(input())
lens = len(strs) while True:
    a,b = map(int,input().split()) #print(a,b)  if 0<=a-1<lens and 0<=b-1<lens: print(longestCommonPrefix([strs[a-1],strs[b-1]]))

第二题ac代码，等第一题的ac出现