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Valid Word

Determine whether a word is valid according to a set of character-count rules.

Acceptance 100%
Problem Statement

Valid Word

Given a word, determine whether it is valid based on a frequency rule over its characters.

A word is considered valid if one of the following is true:

  1. Every character appears the same number of times, or
  2. It can become valid after removing exactly one occurrence of any single character.

Your task is to decide whether the given word is valid.

Notes

  • Treat characters as case-sensitive unless stated otherwise.
  • The exact characters allowed depend on the input format, but the logic should work for any string of lowercase letters or general ASCII characters.
  • If the word is already valid, that also counts as valid.

Input Format

Input

A single string word.

Interpretation

  • Count the frequency of each distinct character in word.
  • Check whether the frequencies are all equal, or can be made equal by deleting one character occurrence.

Output Format

Output

Return true if the word is valid, otherwise return false.

Constraints

  • 1 <= word.length <= $10^{5}$
  • The implementation should be efficient enough to handle large strings.
  • Use O(n)O(n) or near-O(n)O(n) time where possible.
Examples
Sample cases returned by the problem API.

Example 1

Input

word = "aabbcc"

Output

true

Explanation

All characters appear exactly 2 times, so the word is valid.

Example 2

Input

word = "aabbccc"

Output

true

Explanation

Remove one 'c' to make the frequencies 2, 2, 2.

Show 2 more examples

Example 3

Input

word = "aabbc"

Output

true

Explanation

Remove the single 'c' and the remaining frequencies are 2 and 2.

Example 4

Input

word = "aabbcd"

Output

false

Explanation

No single removal can make all remaining character frequencies equal.

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