1582 articles
Solve LeetCode 200 Number of Islands using BFS with a queue or DFS with a stack. The most asked grid interview question at Amazon, Google, Meta, and Microsoft, teaching connected components and flood fill.
Solve LeetCode 207 Course Schedule using Kahn algorithm BFS topological sort with a queue and indegree array. A FAANG interview classic at Amazon, Google, and Meta that tests cycle detection in a directed graph.
Solve LeetCode 210 Course Schedule II by returning an actual topological order using Kahn algorithm BFS or DFS with three colors. A FAANG interview classic at Amazon, Google, Meta, and Microsoft.
Solve LeetCode 127 Word Ladder using BFS with a queue and a wildcard pattern map for O(1) neighbor lookups. A FAANG hard at Amazon, Google, Meta, and Microsoft that tests BFS on implicit graphs.
Solve LeetCode 227 Basic Calculator II using a stack to handle operator precedence for plus, minus, multiplication, and division. A FAANG interview classic at Google, Amazon, Meta, and Uber.