atcoder#AGC036E. [AGC036E] ABC String
[AGC036E] ABC String
Score : points
Problem Statement
Given is a string consisting of A
,B
, and C
.
Consider the (not necessarily contiguous) subsequences of that satisfy all of the following conditions:
A
,B
, andC
all occur the same number of times in .- No two adjacent characters in are the same.
Among these subsequences, find one of the longest. Here a subsequence of is a string obtained by deleting zero or more characters from .
Constraints
- consists of
A
,B
, andC
.
Input
Input is given from Standard Input in the following format:
Output
Print one longest subsequence that satisfies the conditions. If multiple solutions exist, any of them will be accepted.
ABBCBCAB
ACBCAB
Consider the subsequence ACBCAB
of . It satisfies the conditions and is one of the longest with these properties, along with ABCBCA
.
On the other hand, the subsequences ABCBCAB
and ABBCCA
do not satisfy the conditions.
ABABABABACACACAC
BABCAC
ABCABACBCBABABACBCBCBCBCBCAB
ACABACABABACBCBCBCBCA
AAA
It is possible that only the empty string satisfies the condition.