Zipper

Description

Given three strings, you are to determine whether the third string can be formed by combining the characters in the first two strings. The first two strings can be mixed arbitrarily, but each must stay in its original order.

For example, consider forming "tcraete" from "cat" and "tree":

String A: cat
String B: tree
String C: tcraete

As you can see, we can form the third string by alternating characters from the two strings. As a second example, consider forming "catrtee" from "cat" and "tree":

String A: cat
String B: tree
String C: catrtee

Finally, notice that it is impossible to form "cttaree" from "cat" and "tree".
Input

The first line of input contains a single positive integer from 1 through 1000. It represents the number of data sets to follow. The processing for each data set is identical. The data sets appear on the following lines, one data set per line.

For each data set, the line of input consists of three strings, separated by a single space. All strings are composed of upper and lower case letters only. The length of the third string is always the sum of the lengths of the first two strings. The first two strings will have lengths between 1 and 200 characters, inclusive.
Output

For each data set, print:

Data set n: yes

if the third string can be formed from the first two, or

Data set n: no

if it cannot. Of course n should be replaced by the data set number. See the sample output below for an example.
Sample Input

3
cat tree tcraete
cat tree catrtee
cat tree cttaree
Sample Output

Data set 1: yes
Data set 2: yes
Data set 3: no

http://www.kancloud.cn/digest/algorithm123/125312

4级没过的渣渣来看英语也是醉醉哒！好像意思是第一个字符串和第二个字符串乱序合成第三个字符串！如果合成的第三个字符串中，第一个字符串和第二个字符串的顺序没变！那么就是yes，否则是no！难点是相同字符怎么区别吧？值得思考！有趣有趣！