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Find All Anagrams In A String
Find every starting index where a substring is an anagram of a given pattern string.
Acceptance 100%
Problem Statement
Problem
Given two strings s and p, return all starting indices in s where the substring of length |p| is an anagram of p.
A substring is an anagram of p if it uses exactly the same characters with the same frequencies, possibly in a different order.
Notes
- Indices are 0-based.
- Return the indices in increasing order.
- If no substring matches, return an empty list.
Input Format
- A string
s - A string
p
Output Format
- An array of integers representing all valid starting indices
Constraints
- 1 <= |s|, |p| <=
sandptypically contain lowercase English letters- Time-efficient solutions should avoid checking each substring from scratch
Examples
Sample cases returned by the problem API.
Example 1
Input
s = "cbaebabacd", p = "abc"
Output
[0,6]
Explanation
The substrings starting at indices 0 ("cba") and 6 ("bac") are anagrams of "abc".
Example 2
Input
s = "abab", p = "ab"
Output
[0,1,2]
Explanation
The substrings "ab", "ba", and "ab" are all anagrams of "ab".
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