Robina Li

[Medium] 2571. Minimum Operations to Reduce an Integer to 0

Given a positive integer n, you can add or subtract any power of 2 in one operation. Return the minimum...

leetcodemediumbit-manipulation

Apr 19, 2026

[Hard] 2539. Count the Number of Good Subsequences

Given a string s, return the number of non-empty good subsequences of s. A subsequence is good if every character...

leetcodehardcombinatorics

Apr 18, 2026

[Medium] 221. Maximal Square

Given an m x n binary matrix filled with '0's and '1's, find the largest square containing only '1's and...

leetcodemediumdynamic-programming

Apr 18, 2026

[Hard] 329. Longest Increasing Path in a Matrix

Given an m x n integers matrix, return the length of the longest strictly increasing path.

leetcodeharddynamic-programmingdfs

Apr 17, 2026

[Medium] 274. H-Index

Given an array of integers citations where citations[i] is the number of citations a researcher received for their i-th paper,...

leetcodemediumsorting

Apr 16, 2026

[Medium] 92. Reverse Linked List II

Given the head of a singly linked list and two integers left and right where left <= right, reverse the...

leetcodemediumlinked-list

All Posts

Oct 20, 2025

[Medium] 695. Max Area of Island

695. Max Area of Island

leetcodealgorithmmediumdfsgraphmatrix

Oct 20, 2025

[Medium] 1868. Product of Two Run-Length Encoded Arrays

1868. Product of Two Run-Length Encoded Arrays

leetcodealgorithmmediumrun-length-encodingtwo-pointersarray-processing

Oct 20, 2025

Robina Li

Welcome to My Technical Blog

Latest Posts

[Medium] 2571. Minimum Operations to Reduce an Integer to 0

[Hard] 2539. Count the Number of Good Subsequences

[Medium] 221. Maximal Square

[Hard] 329. Longest Increasing Path in a Matrix

[Medium] 274. H-Index

[Medium] 92. Reverse Linked List II

All Posts

[Medium] 695. Max Area of Island

[Medium] 1868. Product of Two Run-Length Encoded Arrays

[Medium] 1570. Dot Product of Two Sparse Vectors

[Medium] 1865. Finding Pairs With a Certain Sum

[Medium] 437. Path Sum III

[Medium] 394. Decode String

[Medium] 417. Pacific Atlantic Water Flow

[Medium] 406. Queue Reconstruction by Height

[Medium] 1856. Maximum Sum of Minimum Product

[Medium] 316. Remove Duplicate Letters