|
Word search II: board DFS guided by a trie
|
|
0
|
0
|
April 21, 2026
|
|
Word search: backtracking with temporary cell marking
|
|
0
|
1
|
April 21, 2026
|
|
Word break: suffix reachability DP
|
|
0
|
0
|
April 21, 2026
|
|
Validate binary search tree: recursive lower-upper bounds
|
|
0
|
0
|
April 21, 2026
|
|
Valid parentheses: stack of expected closing symbols
|
|
0
|
0
|
April 21, 2026
|
|
Valid palindrome: two pointers that skip non-alphanumerics
|
|
0
|
0
|
April 21, 2026
|
|
Valid anagram: frequency-count equality
|
|
0
|
0
|
April 21, 2026
|
|
Unique paths: grid DP with top and left parents
|
|
0
|
0
|
April 21, 2026
|
|
Top k frequent elements: bucket counts by frequency
|
|
0
|
0
|
April 21, 2026
|
|
Sum of two integers: bitwise addition with carry propagation
|
|
0
|
0
|
April 21, 2026
|
|
Subtree of another tree: tree equality check at every candidate root
|
|
0
|
0
|
April 21, 2026
|
|
Spiral matrix: shrink four boundaries inward
|
|
0
|
0
|
April 21, 2026
|
|
Set matrix zeroes: use first row and column as marker storage
|
|
0
|
0
|
April 21, 2026
|
|
Serialize and deserialize binary tree: preorder traversal with null sentinels
|
|
0
|
0
|
April 21, 2026
|
|
Search in rotated sorted array: binary search with sorted-half detection
|
|
0
|
0
|
April 21, 2026
|
|
Same tree: synchronized structural recursion
|
|
0
|
0
|
April 21, 2026
|
|
Rotate image: transpose then reverse each row
|
|
0
|
0
|
April 21, 2026
|
|
Reverse linked list: iterative pointer reversal
|
|
0
|
0
|
April 21, 2026
|
|
Reverse bits: shift-build the answer from left to right
|
|
0
|
0
|
April 21, 2026
|
|
Reorder list: split, reverse second half, weave
|
|
0
|
0
|
April 21, 2026
|
|
Remove nth node from end of list: two pointers with a fixed gap
|
|
0
|
0
|
April 21, 2026
|
|
Product of array except self: prefix and suffix accumulation
|
|
0
|
0
|
April 21, 2026
|
|
Palindromic substrings: count every center expansion
|
|
0
|
0
|
April 21, 2026
|
|
Pacific Atlantic water flow: reverse flood-fill from the oceans
|
|
0
|
0
|
April 21, 2026
|
|
Number of islands: sink each land component once
|
|
0
|
0
|
April 21, 2026
|
|
Number of connected components in an undirected graph: union-find component merging
|
|
0
|
0
|
April 21, 2026
|
|
Number of 1 bits: drop-the-lowest-set-bit loop
|
|
0
|
0
|
April 21, 2026
|
|
Non-overlapping intervals: greedy keep-the-earliest-finish rule
|
|
0
|
0
|
April 21, 2026
|
|
Missing number: XOR cancellation over values and indices
|
|
0
|
0
|
April 21, 2026
|
|
Minimum window substring: two-pointer cover-and-shrink window
|
|
0
|
0
|
April 21, 2026
|