|| ||Code Submission Evaluation System
CSES Problem Set
Task | Statistics
CSES - Subsequence
|Time limit:||1.00 s
||Memory limit:||512 MB|
You are given a DNA sequence that consists of characters A, C, G, and T.
Your task is to find the shortest DNA sequence that is not a subsequence of the original sequence.
The only input line contains a DNA sequence with $n$ characters.
Print the shortest DNA sequence that is not a subsequence of the original sequence. If there are several solutions, you can print any of them.