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题库练习 Erasing Substrings

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A11602 | $Erasing Substrings$

时间限制1s

内存限制256MB

通过 / 提交0/0

题目描述

You are given a string $s$ , initially consisting of $n$ lowercase Latin letters. After that, you perform $k$ operations with it, where ![](/uploads/acgo/image/0d21c21f773bea9c_8965a8f31d71.jpeg). During $i$ -th operation you must erase some substring of length exactly $2^{i-1}$ from $s$ . Print the lexicographically minimal string you may obtain after performing $k$ such operations.

输入格式

The only line contains one string $s$ consisting of $n$ lowercase Latin letters ( $1<=n<=5000$ ).

输出格式

Print the lexicographically minimal string you may obtain after performing $k$ operations.

输入输出样例

输入 #1

adcbca

输出 #1

aba

输入 #2

abacabadabacaba

输出 #2

aabacaba

C++ 编辑器

输入

输出