DSA Roadmap to Leetcode 150+ Problems

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Some considerations while starting with problem solving till 100+ Leetcode problems are solved:

- Start with the most-easiest problems.
- DO NOT try to solve each problem yourself, instead try to learn and understand how different problems are being solved
- Do not try to solve a problem for more than 1 hour initially to get fast and to achieve more in less time, for any problem taking more than 1 hour, put it in a backlog and solve it later
- Average time to solve a problem should be 3-45 minutes
- Do not try to solve a lot of problems from one topic, instead try to solve 5-10 problems per topic
- Do not try to jump into problem solving directly wihtout the necessary pre-requisites, For example
  > If you are trying to solve a problem that requires HashSet/HashMap then make sure you have studied HashMap before solving the problem
  > If you are trying to solve a problem that uses recursion, first make sure you learn recursion properly
  > If you are trying to solve a problem that uses graphs/tree, first make sure you learn graphs/tree properly
  > If you are trying to solve a problem that uses dynamic programming, first make sure you learn dynamic programming properly.
  
  Week 1- Data Structures Overview:
    - Basic Understanding of Data structures in your language (C++ STL, C# Collections, Python Standard Library)
    - If you like C++ and more details > My code school Data Structures
        https://www.youtube.com/playlist?list=PL2_aWCzGMAwI3W_JlcBbtYTwiQSsOTa6P (C++)
     - If you like Python > code basics - Data Structures   
        https://www.youtube.com/playlist?list=PLeo1K3hjS3uu_n_a__MI_KktGTLYopZ12
        
     - Introduction to Hash Tables and Dictionaries by CS Dojo:
        https://www.youtube.com/watch?v=sfWyugl4JWA   
        
    Week 2 - 25 EASY problems ( 3-4 hours a day | 4 problems a day):
      Easy String Algorithms
        - String as character arrays:
            video: https://www.youtube.com/watch?v=TkTgo_7ab0M&pp=ygUQcHJpbnQgY2hhcmFjdGVycw%3D%3D
        - Count characters in string
            video: https://www.youtube.com/watch?v=kWr0TIjO6nU
      - Arrays & Hashing:
          - Contains Duplicate
             video: https://www.youtube.com/watch?v=3OamzN90kPg
             problem: https://leetcode.com/problems/contains-duplicate/
          - Valid Anagram:
              video: https://www.youtube.com/watch?v=9UtInBqnCgA
              problem: https://leetcode.com/problems/valid-anagram/
           - Two Sum:
                video: https://www.youtube.com/watch?v=KLlXCFG5TnA
                problem: https://leetcode.com/problems/group-anagrams/
            - Length of Last word:
                video: https://www.youtube.com/watch?v=KT9rltZTybQ&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=27
                problem:
             - Search Insert Position
                video: https://www.youtube.com/watch?v=K-RYzDZkzCI&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=23
                problem: 
       - Two Pointers:
            - Valid Palindrome
                video: https://leetcode.com/problems/valid-palindrome/         
                problem: https://leetcode.com/problems/valid-palindrome/
             - Best time to buy and Sell Stock:
                video: https://www.youtube.com/watch?v=1pkOgXD63yU&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=7&pp=iAQB
                problem: https://leetcode.com/problems/best-time-to-buy-and-sell-stock/
        - Stack & Queue Problems:
            - Valid Parenthesis
                video: https://www.youtube.com/watch?v=WTzjTskDFMg
                problem: https://leetcode.com/problems/valid-parentheses/
            - Implement Stack using Queue:
                video: https://www.youtube.com/watch?v=rW4vm0-DLYc&list=PLot-Xpze53lfxD6l5pAGvCD4nPvWKU8Qo&index=10
                problem: https://leetcode.com/problems/implement-stack-using-queues/
            - Implement Queue using Stack:
                video: https://www.youtube.com/watch?v=3Et9MrMc02A&pp=ygUabmVldGNvZGUgcXVldWUgdXNpbmcgc3RhY2s%3D
                problem: https://leetcode.com/problems/implement-queue-using-stacks/
            - Sqrt(x)
                problem: https://leetcode.com/problems/sqrtx/
                video:
             - 704. Binary Search
                problem: https://leetcode.com/problems/binary-search/
                video:   
             - 1351. Count Negative Numbers in a Sorted Matrix
                problem:  https://leetcode.com/problems/count-negative-numbers-in-a-sorted-matrix/
                video: 
             - 1351.  Peak Index in a Mountain Array
                problem:  https://leetcode.com/problems/peak-index-in-a-mountain-array/
                video:
             - Find Peak element:
                video: https://www.youtube.com/watch?v=CFgUQUL7j_c   
                problem: 
             - Maximum Sub Array:
                video: https://www.youtube.com/watch?v=5WZl3MMT0Eg&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=4
                problem: https://leetcode.com/problems/maximum-subarray/
      - Linked List:
          course with problems (find all the similar problems on leetcode):
               video: https://www.youtube.com/watch?v=Hj_rA0dhr2I&pp=ygUXbGlua2VkbGlzdCBmcmVlY29kZWNhbXA%3D
          Linked list problems:
             - 206. Reverse Linked List
                https://leetcode.com/problems/reverse-linked-list/
                https://www.youtube.com/watch?v=G0_I-ZF0S38
             - Merge 2 sorted Lits
                https://leetcode.com/problems/merge-two-sorted-lists/
                https://www.youtube.com/watch?v=XIdigk956u0
              - Linked List Cycle
                https://leetcode.com/problems/linked-list-cycle/
                https://www.youtube.com/watch?v=gBTe7lFR3vc
              - Reverse Linked List - Iterative AND Recursive
               video: https://www.youtube.com/watch?v=G0_I-ZF0S38&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=10&pp=iAQB
               code: https://leetcode.com/problems/reverse-linked-list/
              - Palindrome Linked List 
                video: https://www.youtube.com/watch?v=yOzXms1J6Nk&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=13
                problem: 
              - Remove Linked List element:
                  video: https://www.youtube.com/watch?v=JI71sxtHTng&list=PLot-Xpze53lfQmTEztbgdp8ALEoydvnRQ&index=21&pp=iAQB
                  problem: 
                
                
                
    
    

peak ty