Dsa
Strings
Medium
Nested Frequency Expander
You are given a compressed string format where 'n(text)' means the 'text' inside the parentheses should be repeated 'n' times. Nesting can occur to any depth. Your task is to fully expand the string. Numbers are always single digits (1-9) for simplicity, but the resulting string can be long.
Example:
Input: 2(a3(b)c)
Output: abbbbcabbbc
(Explanation: 3(b) becomes bbb. Then 2(abbbc) becomes abbbbcabbbc.)
Key concepts
recursionstackstring-parsing
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