# 14 Days Study Plan to Crack Algo I

2022.03.13

# Day 6

# 3. Longest Substring Without Repeating Characters

Given a string `s`

, find the length of the **longest substring** without repeating characters.

**Example 1:**

**Input:** s = "abcabcbb"

**Output:** 3

**Explanation:** The answer is "abc", with the length of 3.

**Example 2:**

**Input:** s = "bbbbb"

**Output:** 1

**Explanation:** The answer is "b", with the length of 1.

**Example 3:**

**Input:** s = "pwwkew"

**Output:** 3

**Explanation:** The answer is "wke", with the length of 3.

Notice that the answer must be a substring, "pwke" is a subsequence and not a substring.

**Constraints:**

`0 <= s.length <= 5 * 104`

`s`

consists of English letters, digits, symbols and spaces.

# 567. Permutation in String

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:**

**Input:** s1 = "ab", s2 = "eidbaooo"

**Output:** true

**Explanation:** s2 contains one permutation of s1 ("ba").

**Example 2:**

**Input:** s1 = "ab", s2 = "eidboaoo"

**Output:** false

**Constraints:**

`1 <= s1.length, s2.length <= 104`

`s1`

and`s2`

consist of lowercase English letters.