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   "markdown-importer",
   "outline",
   "word-count",
-  "open-with-default-app",
   "file-recovery"
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diff --git a/OJ notes/pages/Leetcode Longest-Substring-Without-Repeating-Characters.md b/OJ notes/pages/Leetcode Longest-Substring-Without-Repeating-Characters.md
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+# Leetcode Longest-Substring-Without-Repeating-Characters
+
+#### 2022-07-14 09:33
+
+> ##### Algorithms:
+> #algorithm 
+> ##### Data structures:
+> #DS #string 
+> ##### Difficulty:
+> #coding_problem #difficulty-medium 
+> ##### Additional tags:
+> #leetcode 
+> ##### Revisions:
+> N/A
+
+##### Related topics:
+```expander
+tag:#<INSERT_TAG_HERE>
+```
+ 
+ 
+
+##### Links:
+- [Link to problem](https://leetcode.com/problems/longest-substring-without-repeating-characters/)
+___
+### Problem
+
+Given a string `s`, find the length of the **longest substring** without repeating characters.
+
+#### Examples
+
+**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.
+
+### Thoughts
+
+> [!summary]
+> This is a #
+
+Initially, I thought of a lineal algorithm
+
+### Solution
+
+Initial solution
+
+```cpp
+class Solution {
+public:
+  int lengthOfLongestSubstring(string s) {
+    unordered_map<char, int> hMap;
+    int cur = 0;
+    int localMax = 0;
+
+    for (int i = 0; i < s.size(); i++) {
+      if (hMap.find(s[i]) == hMap.end()) {
+        cur++;
+        localMax = max(cur, localMax);
+        hMap[s[i]] = i;
+      } else {
+        i = hMap[s[i]];
+        hMap.clear();
+        cur = 0;
+      }
+    }
+    return localMax;
+  }
+};
+```
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