摘要:
Given a binary tree, return the values of its boundary in anti-clockwise direction starting from root. Boundary includes left boundary, leaves, and ri 阅读全文
摘要:
Given an unsorted integer array, find the smallest missing positive integer. Example 1: Example 2: Example 3: Note: Your algorithm should run in O(n) 阅读全文
摘要:
A virus is spreading rapidly, and your task is to quarantine the infected area by installing walls. The world is modeled as a 2-D array of cells, wher 阅读全文