Asterisk-Minor Template

题意翻译

定义一个字符串的模板 $T$，其中仅包含小写字母和可以代替任意字符串（包括空字符串）的通配符 '\*'。一个合法的模板需要满足 '\*' 的数量小于等于小写字母的数量。 有一个仅包含小写字母的字符串 $s$，如果我们可以选择出一个合法的模板 $T$，可以通过替换所有的 '\*' 使其等于 $s$，则称字符串 $s$ 与模板 $T$ 匹配。 现在有 $t$ $(1 \le t \le 10^4) $ 组询问，每次给出两个仅包含小写字母的字符串 $a,b$ $(1\le|a|,|b|\le 50)$，请给出一个合法的模板 $T$ 使其能同时匹配两个字符串，或输出无解 "NO"。

题目描述

You are given two strings $ a $ and $ b $ , consisting of lowercase Latin letters. A template $ t $ is string, consisting of lowercase Latin letters and asterisks (character '\*'). A template is called asterisk-minor if the number of asterisks in it is less than or equal to the number of letters in it. A string $ s $ is said to be matching a template $ t $ if you can replace each asterisk in $ t $ with a string of lowercase Latin letters (possibly, an empty string) so that it becomes equal to $ s $ . Find an asterisk-minor template such that both $ a $ and $ b $ match it, or report that such a template doesn't exist. If there are multiple answers, print any of them.

输入输出格式

输入格式

The first line contains a single integer $ t $ ( $ 1 \le t \le 10^4 $ ) — the number of testcases. The first line of each testcase contains a string $ a $ ( $ 1 \le |a| \le 50 $ , where $ |a| $ is the length of $ a $ ), consisting of lowercase Latin letters. The second line contains a string $ b $ ( $ 1 \le |b| \le 50 $ ), consisting of lowercase Latin letters.

输出格式

For each testcase, output "NO", if there doesn't exist an asterisk-minor template that both $ a $ and $ b $ match. Otherwise, print "YES" in the first line and the template in the second line. If there are multiple answers, print any of them. A template should consist only of lowercase Latin letters and asterisks (character '\*'). The number of asterisks should be less than or equal to the number of letters.

输入输出样例

输入样例 #1

6
aaab
zzzb
codeforces
atcoder
codeforces
tokitlx
aaaa
aaaaaa
abcd
abcd
c
f

输出样例 #1

YES
*b
YES
*co*
NO
YES
a*a*a*a
YES
abcd
NO

说明

In the first testcase, for a template "\*b", you can replace the only asterisk with "aaa" to get "aaab" (which is equal to $ a $ ) or with "zzz" to get "zzzb" (which is equal to $ b $ ). In the third testcase, a template "\*o\*" is not asterisk-minor, as it contains more asterisks than letters. There are no asterisk-minor templates that both $ a $ and $ b $ match. In the fourth testcase, for a template "a\*a\*a\*a", you can replace all asterisks with empty strings to get "aaaa" (which is equal to $ a $ ) or two of them with "a" and two of them with an empty string to get "aaaaaa" (which is equal to $ b $ ). In the fifth testcase, there are no asterisks in a template "abcd", so only "abcd" can match it (which is coincidentally both $ a $ and $ b $ ).

题意翻译

定义一个字符串的模板 $T$，其中仅包含小写字母和可以代替任意字符串（包括空字符串）的通配符 '\*'。一个合法的模板需要满足 '\*' 的数量小于等于小写字母的数量。 有一个仅包含小写字母的字符串 $s$，如果我们可以选择出一个合法的模板 $T$，可以通过替换所有的 '\*' 使其等于 $s$，则称字符串 $s$ 与模板 $T$ 匹配。 现在有 $t$ $(1 \le t \le 10^4) $ 组询问，每次给出两个仅包含小写字母的字符串 $a,b$ $(1\le|a|,|b|\le 50)$，请给出一个合法的模板 $T$ 使其能同时匹配两个字符串，或输出无解 "NO"。