#+ANKI_DECK: study_deck_02
* TODO 0567. Permutation In String :medium:
:PROPERTIES:
:NEETCODE: [[file:../../roadmap.org::*0567. Permutation In String][0567. Permutation In String]]
:END:

Given two strings ~s1~ and ~s2~, return ~true~ if ~s2~ contains a permutation of ~s1~, or ~false~ otherwise.

In other words, return ~true~ if one of ~s1~'s permutations is the substring of ~s2~.

*Example 1:*


#+begin_src
Input: s1 = "ab", s2 = "eidbaooo"
Output: true
Explanation: s2 contains one permutation of s1 ("ba").
#+end_src


*Example 2:*


#+begin_src
Input: s1 = "ab", s2 = "eidboaoo"
Output: false
#+end_src


*Constraints:*

 - ~1 <= s1.length, s2.length <= 10^{4}~

 - ~s1~ and ~s2~ consist of lowercase English letters.

** TODO Approach
Write your approach here.

** TODO Python
#+begin_src python
class Solution:
    def checkInclusion(self, s1: str, s2: str) -> bool:
#+end_src

** TODO C++
#+begin_src cpp
class Solution {
public:
    bool checkInclusion(string s1, string s2) {
        
    }
};
#+end_src