\(5^{th}\) round, February \(15^{th}\), 2014

Mirko likes to play with strings of characters, but this time he has taken it too far – he put an
“explosion” in the string! An explosion is a series of characters which, if found in the vicinity of fire,
explodes and starts a chain reaction.
Mirko, being as negligent as he usually is, forgot that his string contained an explosion and placed it
near a candlelight. Thus the chain reaction began.
The chain reaction takes place in the following way:
• if a string contains explosions, they all explode and a new string is formed by concatenating the
pieces without the exploding parts
• this concatenation could possibly create new explosions
• the chain reaction repeats while there are explosions in the string
Now Mirko wants to know whether anything will be left after this series of chain reactions. If nothing
remains, output “FRULA” (without quotes). If, by any chance, something is left, output the final
string remaining after all the reactions.
Please note: The explosion will not contain two equal characters.

In test cases worth 50% of total points, N will not exceed 3000.

The first line of input contains Mirko's string, (1 ≤ |Mirko's string| ≤ 1 000 000).
The second line of input contains the explosion string, (1 ≤ |explosion| ≤ 36).
Both Mirko's string and the explosion string consist of uppercase and lowercase letters of the English
alphabet and digits 0, 1, ... 9.

The first and only line of output must contain the final string remaining after all the reactions as stated
in the task.

생성자가 기록되지 않았습니다.

출처 COCI 2013/2014 Contest 5