non repat substr

Author: sachuverma

Striver Sheet/Day-4/Longest Substring Without Repeating Characters.cpp

@@ -0,0 +1,55 @@
+/*
+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.
+
+Example 4:
+Input: s = ""
+Output: 0
+
+Constraints:
+0 <= s.length <= 5 * 104
+s consists of English letters, digits, symbols and spaces.
+*/
+
+class Solution
+{
+public:
+  int lengthOfLongestSubstring(string s)
+  {
+    int i = 0, j = 0;
+    int n = s.size(), ans = 0;
+
+    vector<int> freq(256, 0);
+    while (i < n && j < n)
+    {
+      while (freq[s[j]] > 0)
+      {
+        freq[s[i]]--;
+        i++;
+      }
+      freq[s[j]]++;
+      j++;
+      ans = max(ans, j - i);
+    }
+
+    return ans;
+  }
+};

Striver Sheet/README.md

@@ -36,7 +36,7 @@
 - [Longest Consecutive Sequence](https://leetcode.com/problems/longest-consecutive-sequence/) - [Cpp Soultion](./Day-4/Longest%20Consecutive%20Sequence.cpp)
 - [Largest subarray with 0 sum](https://practice.geeksforgeeks.org/problems/largest-subarray-with-0-sum/1#) - [Cpp Soultion](./Day-4/Largest%20subarray%20with%200%20sum.cpp)
 - []() - [Cpp Soultion](./Day-4/.cpp)
-- []() - [Cpp Soultion](./Day-4/.cpp)
+- [Longest Substring Without Repeating Characters](https://leetcode.com/problems/longest-substring-without-repeating-characters/) - [Cpp Soultion](./Day-4/Longest%20Substring%20Without%20Repeating%20Characters.cpp)
 
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