JZLeetCode

High quality leet code solutions in Java, Python, C++, and Rust.

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Featured

• LeetCode 200 Number of Islands

  10 Apr, 2026

  Solutions for LeetCode 200, medium, tags: array, depth-first search, breadth-first search, union find, matrix.

• LeetCode 739 Daily Temperatures

  10 Apr, 2026

  Solutions for LeetCode 739, medium, tags: array, stack, monotonic stack.

• LeetCode 3 Longest Substring Without Repeating Characters

  9 Apr, 2026

  Solutions for LeetCode 3, medium, tags: hash table, string, sliding window.

• LeetCode 378 LintCode 1272 Kth Smallest Element in a Sorted Matrix

  8 Apr, 2026

  Solutions for LeetCode 378 and LintCode 1272, medium, tags: array, binary search, heap, matrix.

• LeetCode 3653 XOR After Range Multiplication Queries I

  7 Apr, 2026

  Solutions for LeetCode 3653, medium, tags: array, simulation.

• LeetCode 874 Walking Robot Simulation

  5 Apr, 2026

  Solutions for LeetCode 874, medium, tags: array, hash table, simulation.

• LeetCode 631 Design Excel Sum Formula

  4 Apr, 2026

  Solutions for LeetCode 631, hard, tags: design, graph, depth-first search, topological sort.

• LeetCode 721 Accounts Merge

  31 Mar, 2026

  Solutions for LeetCode 721, medium, tags: array, hash table, string, depth-first search, breadth-first search, union find, sorting.

• LeetCode 638 Shopping Offers

  28 Mar, 2026

  Solutions for LeetCode 638, medium, tags: array, dynamic programming, backtracking, bitmask, memoization.