LeetcodeTwo Pointers
3Sum: Fix One Element, Reduce to Two Sum with Two Pointers
Learn why 3Sum reduces to sorted Two Sum. Interactive visualizer shows how fixing one element and using two pointers drops O(n³) to O(n²).
12 min read
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Leetcode
Crack the code, ace the interview
10 posts
LeetcodeTwo Pointers
Trapping Rain Water: Why the Shorter Wall Controls Everything
Learn why water at each bar depends on its tallest neighbors. Interactive visualizer shows how two pointers find trapped water in one pass.
10 min read
LeetcodeTwo Pointers
Container With Most Water: The Two-Pointer Pattern That Shrinks O(n²) to O(n)
Learn why the shorter wall limits everything. Interactive visualizer shows how two pointers eliminate entire rows of possibilities in one pass.
10 min read
LeetcodeArrays
Next Permutation: Visualizing the Lexicographical Step
See why Next Permutation is about finding the rightmost ascent. Interactive visualizer shows how one scan from the right transforms O(n!) brute force into O(n).
9 min read
LeetcodeArrays
Two Sum: The Hash Map Trick That Drops O(n²) to O(n)
See why Two Sum is just an existence check. Interactive visualizer shows how one equation turns O(n²) brute force into O(n) with hash maps.
8 min read
LeetcodeBinary Search
Binary Search: Visualizing Why O(log n) Feels Like Magic
Visualize why O(log n) feels like magic. Watch binary search rip through a phonebook while linear search flips page by page.
8 min read
LeetcodeTrees
Level Order Traversal: See BFS Spread Like a Sound Wave
Watch BFS spread like a sound wave while DFS dives like a snake. Interactive visual included.
7 min read
LeetcodeRecursion
Why Recursion Burns Your CPU (And How Memoization Fixes It)
Visualize why naive recursion explodes exponentially. Watch memoization turn chaos into order with an interactive Fibonacci simulator.
9 min read
LeetcodeArrays
Sliding Window Algorithm: Why O(n²) is Just Bad Memory
Visualize why O(n²) is inefficient through a heat map simulator. Watch brute force burn CPU cycles while sliding window glides smoothly.
15 min read
LeetcodeRecursion
Backtracking Explained: Watch the Algorithm Pick a Lock
Visualize backtracking through an interactive lock picker simulator. Watch how state reversibility saves memory while brute force creates infinite universes.
9 min read