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