Vandalism
시간 제한1초메모리 제한2048 MB
문자열 UAPC에서 일부 문자를 지워 만든 부분수열이 주어질 때, 지워진 문자를 원래 순서대로 출력한다.
문제
In recent weeks, the United Association against Property Crime (UAPC) sign has been repeatedly vandalized. Vandals remove some of the letters from UAPC to form an acronym of their choosing. For example, last month, the Unauthorized Art Collective (UAC) removed the letter P.
The UAPC is tired of manually determining which letters have been lost and need replacement. They have tasked you with creating an algorithm to automatically identify the missing letters.
입력
The first line of input contains a string of length at most . It is guaranteed that is non-empty and can be obtained by removing some characters from UAPC, while preserving the order of the remaining letters. It is guaranteed that at least one character has been removed.
출력
Output a string consisting of the characters removed from UAPC to obtain , listed in the order they appear in UAPC.