Unique Folder Names

Medium

Folders are created one by one, and requests[i] is the name asked for the i-th folder. No two folders may share a name. If the requested name is still free, the folder gets it. Otherwise the system appends a suffix (k) with the smallest integer k ≥ 1 that makes the name free. For example, if photo and photo(1) are taken, a new photo becomes photo(2). Return the names the folders actually receive, in creation order.

Example 1

requests=["notes", "draft", "notes", "notes(1)"] → ['notes', 'draft', 'notes(1)', 'notes(1)(1)']

The third "notes" is taken and becomes "notes(1)". The fourth asks for "notes(1)", which is now taken, so it becomes "notes(1)(1)".

Example 2

requests=["img", "img(2)", "img", "img"] → ['img', 'img(2)', 'img(1)', 'img(3)']

The second request for "img" gets "img(1)"; the third skips the taken "img(2)" and gets "img(3)".

Constraints

1 ≤ len(requests) ≤ 5 · 10⁴
1 ≤ len(requests[i]) ≤ 20
Names consist of lowercase English letters, digits and round brackets

Have you seen this problem in a real interview?

Solved by0

Tried by0

Submissions0

Acceptance—

Topics

Array Hash Table String

Similar problems

Anagram Buckets Medium Split Into Dictionary Words Medium Words Equal Up to a Shift Medium A Subsequence of One Word Only Medium Files With the Same Content Medium

Input

requests=["notes", "draft", "notes", "notes(1)"]

Expected

['notes', 'draft', 'notes(1)', 'notes(1)(1)']

Run checks the first 3 tests in your browser. Submit checks all 68 tests on the server, hidden ones included.