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Problem Challenge 2: String Anagrams (hard)

Problem Statement

Given a string and a pattern, find all anagrams of the pattern in the given string.

Every anagram is a permutation of a string. As we know, when we are not allowed to repeat characters while finding permutations of a string, we get N! permutations (or anagrams) of a string having N characters. For example, here are the six anagrams of the string abc:

  1. abc
  2. acb
  3. bac
  4. bca
  5. cab
  6. cba

Write a function to return a list of starting indices of the anagrams of the pattern in the given string.

Example 1:

Input: str="ppqp", pattern="pq"  
Output: [1, 2]  
Explanation: The two anagrams of the pattern in the given string are "pq" and "qp".

Example 2:

Input: str="abbcabc", pattern="abc"  
Output: [2, 3, 4]  
Explanation: The three anagrams of the pattern in the given string are "bca", "cab", and "abc".

Constraints:

  • 1 <= s.length, p.length <= 3 * 10<sup>4</sup>
  • str and pattern consist of lowercase English letters.

Try it yourself

Try solving this question here:

Python3
Python3
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