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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.

 class Solution:
    def lengthOfLongestSubstring(self, s: str) -> int:
        max_length = 0
        hashset = set()
        wordlist = []

        for c in s:
            if c in hashset:
                max_length = max(len(hashset), max_length)

                removed_char = wordlist.pop(0)
                hashset.remove(removed_char)
                while(removed_char!=c):
                    removed_char = wordlist.pop(0)
                    hashset.remove(removed_char)

                hashset.add(c)
                wordlist.append(c)

            else:
                hashset.add(c)
                wordlist.append(c)

                max_length = max(len(hashset), max_length)

        return max_length

𝗦𝘆𝘀𝘁𝗲𝗺 𝗗𝗲𝘀𝗶𝗴𝗻 𝗞𝗲𝘆 𝗖𝗼𝗻𝗰𝗲𝗽𝘁𝘀:

  1. Scalability: https://lnkd.in/gpge_z76
  2. Latency vs Throughput: https://lnkd.in/g_amhAtN
  3. CAP Theorem: https://lnkd.in/g3hmVamx
  4. ACID Transactions: https://lnkd.in/gMe2JqaF
  5. Rate Limiting: https://lnkd.in/gWsTDR3m
  6. API Design: https://lnkd.in/ghYzrr8q
  7. Strong vs Eventual Consistency: https://lnkd.in/gJ-uXQXZ
  8. Distributed Tracing: https://lnkd.in/d6r5RdXG
  9. Sync vs Async Communication: https://lnkd.in/gC3F2nvr
  10. Batch vs Stream Processing: https://lnkd.in/g4_MzM4s
  11. Fault Tolerance: https://lnkd.in/dVJ6n3wA

𝗦𝘆𝘀𝘁𝗲𝗺 𝗗𝗲𝘀𝗶𝗴𝗻 𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗕𝗹𝗼𝗰𝗸𝘀:

  1. Database: https://lnkd.in/gti8gjpz
  2. Horizontal vs Vertical Scaling: https://lnkd.in/gAH2e9du
  3. Caching: https://lnkd.in/gC9piQbJ
  4. Distributed Caching: https://lnkd.in/g7WKydNg
  5. Load Balancing: https://lnkd.in/gQaa8sXK
  6. SQL vs NoSQL: https://lnkd.in/g3WC_yxn
  7. Database Scaling: https://lnkd.in/gAXpSyWQ
  8. Data Replication: https://lnkd.in/gVAJxTpS
  9. Data Redundancy: https://lnkd.in/gNN7TF7n
  10. Database Sharding: https://lnkd.in/gMqqc6x9
  11. Database Indexes: https://lnkd.in/gCeshYVt
  12. Proxy Server: https://lnkd.in/gi8KnKS6
  13. WebSocket: https://lnkd.in/g76Gv2KQ
  14. API Gateway: https://lnkd.in/gnsJGJaM
  15. Message Queues: https://lnkd.in/gTzY6uk8

𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗮𝗹 𝗣𝗮𝘁𝘁𝗲𝗿𝗻𝘀:

  1. Event-Driven Architecture: https://lnkd.in/dp8CPvey
  2. Client-Server Architecture: https://lnkd.in/dAARQYzq
  3. Serverless Architecture: https://lnkd.in/gQNAXKkb
  4. Microservices Architecture: https://lnkd.in/gFXUrz_T

𝗟𝗼𝘄-𝗟𝗲𝘃𝗲𝗹 𝗗𝗲𝘀𝗶𝗴𝗻 𝗣𝗿𝗼𝗯𝗹𝗲𝗺𝘀:

  1. Design Parking Lot: https://lnkd.in/dQaAuFd2
  2. Design Splitwise: https://lnkd.in/dF5fBnex
  3. Design Chess Validator: https://lnkd.in/dfAQHvN4
  4. Design Distributed Queue | Kafka: https://lnkd.in/dQ6_B4_M

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