ThinkerQAQ

Data Structures & Algorithms

237 notes

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  1. Two Sumhistorical

    LeetCode notes on the Two Sum problem.

    leetcode / 数组 / map / N数之和
  2. Find All Numbers Disappeared in an Arrayhistorical

    LeetCode notes on finding all disappeared numbers in an array.

    leetcode / 数组 / map / 原地Hash
  3. Big Number Additionhistorical

    Add large numbers represented as strings by scanning from right to left and carrying.

    leetcode / 字符串
  4. Subarray Sum Equals Khistorical

    LeetCode notes on the Subarray Sum Equals K problem.

    leetcode / 数组 / map / N数之和
  5. Longest Consecutive Sequencehistorical

    LeetCode notes on the Longest Consecutive Sequence problem.

    leetcode / 数组 / map
  6. Decode Stringhistorical

    Decode strings in k[encoded_string] form using a stack.

    leetcode / 字符串 / 栈
  7. Longest Valid Parentheseshistorical

    Use a stack to mark matched parentheses, then count the longest consecutive valid interval.

    leetcode / 字符串 / 栈
  8. Remove Invalid Parentheseshistorical

    Enumerate whether to keep or remove each character, then keep the longest valid-parentheses results.

    leetcode / 字符串 / 栈 / DFS
  9. Generate Parentheseshistorical

    Generate parentheses using full enumeration with a stack, and pruning based on remaining left/right parentheses.

    leetcode / 字符串 / 栈 / DFS
  10. Valid Parentheseshistorical

    Validate a parentheses sequence using a stack or repeated string replacement.

    leetcode / 字符串 / 栈