My Journey of Self-Studying Data Structures & Algorithms again !! NO VIBECODINGGG

Day	Problem	Level	Status	Runtime	Memory	Notes
1	704. Binary Search	Easy	Solved	0ms (Beats 100%)	57MB (Beats 96.24%)	Perfect optimization
2	34. Find First and Last Position of Element in Sorted Array	Medium	Solved	0ms (Beats 100%)	56.51MB (Beats 32.65%)	This is a very good problem that requires an auxiliary function to find the boundary
3	1929. Concatenation of Array	Easy	Solved	1ms (Beats 90%)	59.50MB (Beats 55.72%)	Array manipulation, Dynamic Array O(N), Modulo trick %, has 4 ways to solve this problem
4	26. Remove Duplicates from Sorted Array	Easy	Solved	0ms (Beats 100%)	58.50MB (Beats 64.85%)	This problem i use Two Pointers to solve
4	27. Remove Element	Easy	Solved	0ms (Beats 100.00%)	54.86MB (Beats 73.54%)	Similar to LC26, using Slow & Fast Pointers for In-place modification
5	14. Longest Common Prefix	Easy	Solved	0ms (Beats 100%)	52.34MB (Beats 85.12%)	Classic string problem, solved using prefix shrinking technique
5	121. Best Time to Buy and Sell Stock	Easy	Solved	1ms (Beats 95.09%)	65.76MB (Beats 62.09%)	Greedy approach: track minPrice and update maxProfit
6	35. Search Insert Position	Easy	Solved	0ms (Beats 100.00%)	54.87MB (Beats 79.18%)	O(log N) Binary Search. Mastered the Loop Invariant concept to return left as the exact insertion index
6	33. Search in Rotated Sorted Array	Medium	Solved	1ms (Beats 16.40%)	54.91MB (Beats 77.49%)	Modified O(log N) Binary Search. Core logic: Identify the "sorted half" first, then check if the target falls within its boundaries
7	153. Find Minimum in Rotated Sorted Array	Medium	Solved	0ms (Beats 100.00%)	54.12MB (Beats 80.50%)	O(log N) Binary Search Template 2 (left < right). Core logic: Compare nums[mid] with nums[right] to locate the pivot (minimum element)
8	875. Koko Eating Bananas	Medium	Solved	1ms (Beats 99.00%)	55.40MB (Beats 89.20%)	Binary Search on Answer (in range). Core logic: Use BS on the range of possible speeds [1, max(piles)]. Created a helper function checkSpeed(k) to test if Koko can finish in time, leveraging monotonic true/false boundary. Time: O(N * log M).
9	🚀 REVIEW DAY: Pattern Consolidation	ALL	Reviewed	-	-	Spaced Repetition Day! Blind re-coded all patterns: Binary Search (Templates 1 & 2, On Answer), Two Pointers, and Array Manipulation. Solidifying the T-Shaped JS/TS foundation.
10	66. Plus One	Easy	Solved	0ms (Beats 100%)	55.20MB (Beats 80.00%)	Array Implementation. Right-to-left traversal simulating addition. Handled the 9s domino effect and unshift(1) edge case for overflow. Time: O(N), Space: O(1).
11	206. Reverse Linked List	Easy	Solved	0ms (Beats 100.00%)	57.85MB (Beats 87.71%)	Linked List In-place Reversal. Mastered the 4-step pointer swap (prev, current, nextTemp). Time: O(N), Space: O(1).
12	167. Two Sum II - Input Array Is Sorted	Medium	Solved	0ms (Beats 100.00%)	50.32MB (Beats 86.40%)	Two Pointers (Opposite Direction). Exploited the "Sorted" property to squeeze left and right towards the center. Time: O(N), Space: O(1). Returned 1-indexed values.
12	15. 3Sum	Medium	Solved	41ms (Beats 40,59%)	73.92MB (Beats 34.56%)	Sorting + Two Pointers. Transformed into Two Sum II by anchoring a (via for loop) and squeezing left/right. Mastered skipping duplicates for all 3 pointers. Time: O(N²), Space: O(1).
13	11. Container With Most Water	Medium	Solved	3ms (Beats 37.84%)	64.01MB (Beats 23.43%)	Two Pointers (Greedy approach). Placed pointers at both ends to maximize width, then moved the pointer with the lower height inward to find a potentially higher boundary. Time: O(N), Space: O(1).
14	42. Trapping Rain Water	Hard	Solved	[Chờ LC]	[Chờ LC]	Two Pointers. Tracked maxLeft and maxRight from both ends, calculating trapped water based on the shorter bounding wall. The ultimate boss of Two Pointers pattern. Time: O(N), Space: O(1).
15	🧠 REVIEW DAY: Two Pointers Mastery	ALL	Reviewed	-	-	Deep Dive: Blind re-coded LC167, LC15, LC11. Solidified the "move pointers inward to eliminate" strategy and mastered duplicate skipping logic without looking at past solutions.
16	🔥 Edge Case Review Day	ALL	Completed	-	-	Final Boss Recap: Ôn tập lại LC42 (Trapping Rain Water). Trace biến maxLeft, maxRight trên giấy cho các tình huống khó. Xác nhận tư duy tối ưu O(1) space và phân tích Time/Space Complexity.