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Abzal Khairullauly

LeetCode

Problems I've solved, and notes on how: the approach, the mistakes I made and what I still need to re-drill.

Solved on LeetCode

43problems solved

Easy
31
Medium
11
Hard
1

As of

Notes 4

  • 20.Valid ParenthesesEasy

    Given a string of ()[]{} characters, decide whether every bracket is closed by the same type of bracket, in the right order.

    stack matching

  • 21.Merge Two Sorted ListsEasy

    Merge two sorted linked lists into one sorted list by splicing their nodes together, and return its head.

    two pointers + dummy node

  • 151.Reverse Words in a StringMedium

    Given a string s, reverse the order of the words (not characters). Words are separated by spaces; input may contain leading/trailing/multiple spaces which must be collapsed into single spaces in the output.

    string split / two pointers

  • 206.Reverse Linked ListEasy

    Reverse a singly linked list and return the new head.

    in-place pointer reversal

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