题目

The Japanese language is notorious for its sentence ending particles. Personal preference of such particles can be considered as a reflection of the speaker’s personality. Such a preference is called “Kuchiguse” and is often exaggerated artistically in Anime and Manga. For example, the artificial sentence ending particle “nyan~” is often used as a stereotype for characters with a cat-like personality:

  • Itai nyan~ (It hurts, nyan~)
  • Ninjin wa iyada nyan~ (I hate carrots, nyan~)

Now given a few lines spoken by the same character, can you find her Kuchiguse?

Input Specification:

Each input file contains one test case. For each case, the first line is an integer N (2≤N≤100). Following are N file lines of 0~256 (inclusive) characters in length, each representing a character’s spoken line. The spoken lines are case sensitive.

Output Specification:

For each test case, print in one line the kuchiguse of the character, i.e., the longest common suffix of all N lines. If there is no such suffix, write nai.

Sample Input 1:

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Itai nyan~
Ninjin wa iyadanyan~
uhhh nyan~

Sample Output 1:

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nyan~

Sample Input 2:

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Itai!
Ninjinnwaiyada T_T
T_T

Sample Output 2:

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nai

题解

思路

  • 题目的意思是让我们找字符串的公共后缀
  • 我们可以先把它们逆序，求前缀，方便一点。
  • 直接遍历每一个字符串的第0个字符，看看是不是都相等
  • 相等了，添加进答案里，然后遍历第1个字符，以此类推
  • 当发现了不符合的或者字符下标超过了字符串长度的时候，退出
  • 输出答案即可

数据结构

  • lines 是一个列表，存放所有逆序的字符串们
  • i指示字符串的下标

算法

  • 将逆序后的字符串们放到lines当中
  • 从0开始遍历下标，遍历每一个字符串
  • 如果有一个字符串的下标位置的字符和第0个字符串的下标位置的值不一样，或者下标超过了一个字符串的长度
  • 那么直接退出。
  • 否则把这个字符添加进答案。
  • 这里使用了judge()作为一个函数的目的是跳出两层循用一个return即可，很方便。直接用break的话只能跳出一层。
  • 将答案逆序输出。

代码

  • 因为使用Python3能AC，因此只放了Python的代码。
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num = int(input())
lines = []
ans = []
for _ in range(num):
    lines.append(input()[::-1])


def judge():
    for i in range(0, 999):
        for line in lines:
            if len(line) < i or line[i] != lines[0][i]:
                return
        else:
            ans.append(lines[0][i])
    return


judge()
if not ans:
    print("nai")
else:
    print("".join(ans[::-1]))