Browse every published problem solving article in Data Structures & Algorithms.
Data Structures & Algorithms · Problem Solving
Count connected regions of land with iterative depth-first search, track visited cells, and implement Number of Islands in C#, Go, and Python 3.
Data Structures & Algorithms · Problem Solving
Reverse a signed integer one digit at a time, detect 32-bit overflow before it happens, and handle negative numbers in C#, Go, and Python 3.
![The brackets {[()]} with the round pair highlighted, beside a stack holding {, [ and ( where ( is popped before the closing )](/_image?href=%2F_astro%2Fcover.R2rUE-K4.png&w=800&h=450&q=mid&f=webp&fit=cover)
Data Structures & Algorithms · Problem Solving
Updated
Learn why bracket order needs a stack, trace a linear-time solution, and implement Valid Parentheses in C#, Go, and Python 3.
Data Structures & Algorithms · Problem Solving
Find a target in a sorted array with binary search, using an inclusive search range and O(log n) time.
Data Structures & Algorithms · Problem Solving
Improve Two Sum from nested loops to a single pass using a dictionary, with C#, Go, and Python 3 examples.