Programming contests

ECN selejtező programozó csapatverseny, 2016. március 23.

March 23, 2016 10:10 AM – March 23, 2016 3:10 PM

Zipper

Given three strings, you are to determine whether the third string can be formed by combining the characters of the first two strings. The characters of 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 Specification

The first line of the 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 uppercase and lowercase 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 Specification

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

1. `3`
2. `cat tree tcraete`
3. `cat tree catrtee`
4. `cat tree cttaree`
1. `Data set 1: yes`
2. `Data set 2: yes`
3. `Data set 3: no`