## Leetcode - Permutation in String

https://leetcode.com/problems/permutation-in-string/

Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string.

Example 1:

```Input: s1 = "ab" s2 = "eidbaooo"
Output: True
Explanation: s2 contains one permutation of s1 ("ba").
```

Example 2:

```Input:s1= "ab" s2 = "eidboaoo"
Output: False
```

## Leetcode - Find All Anagrams in a String

https://leetcode.com/problems/find-all-anagrams-in-a-string/

Given a string s and a non-empty string p, find all the start indices of p's anagrams in s.

Strings consists of lowercase English letters only and the length of both strings s and p will not be larger than 20,100.

The order of output does not matter.

Example 1:

```Input:
s: "cbaebabacd" p: "abc"

Output:
[0, 6]

Explanation:
The substring with start index = 0 is "cba", which is an anagram of "abc".
The substring with start index = 6 is "bac", which is an anagram of "abc".
```

## Leetcode - Longest Substring with At Most K Distinct Characters

https://leetcode.com/problems/longest-substring-with-at-most-k-distinct-characters/

Given a string, find the length of the longest substring T that contains at most k distinct characters.

Example 1:

```Input: s = "eceba", k = 2
Output: 3
Explanation: T is "ece" which its length is 3.```

Example 2:

```Input: s = "aa", k = 1
Output: 2
Explanation: T is "aa" which its length is 2.
```

## Leetcode - Minimum Window Substring

https://leetcode.com/problems/minimum-window-substring/

Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).

Example:

```Input: S = "ADOBECODEBANC", T = "ABC"
Output: "BANC"
```

Note:

• If there is no such window in S that covers all characters in T, return the empty string `""`.
• If there is such window, you are guaranteed that there will always be only one unique minimum window in S.

## Leetcode - Find K-Length Substrings With No Repeated Characters

https://leetcode.com/problems/find-k-length-substrings-with-no-repeated-characters/

Given a string `S`, return the number of substrings of length `K` with no repeated characters.

Example 1:

```Input: S = "havefunonleetcode", K = 5
Output: 6
Explanation:
There are 6 substrings they are : 'havef','avefu','vefun','efuno','etcod','tcode'.
```

Example 2:

```Input: S = "home", K = 5
Output: 0
Explanation:
Notice K can be larger than the length of S. In this case is not possible to find any substring.
```

## Leetcode - Minimum Size Subarray Sum

https://leetcode.com/problems/minimum-size-subarray-sum/

Given an array of n positive integers and a positive integer s, find the minimal length of a contiguous subarray of which the sum ≥ s. If there isn't one, return 0 instead.

Example:

```Input: `s = 7, nums = [2,3,1,2,4,3]`
Output: 2
Explanation: the subarray `[4,3]` has the minimal length under the problem constraint.```