463. Island Perimeter

2018-08-25

Problem description:

You are given a map in form of a two-dimensional integer grid where 1 represents land and 0 represents water. Grid cells are connected horizontally/vertically (not diagonally). The grid is completely surrounded by water, and there is exactly one island (i.e., one or more connected land cells). The island doesn’t have “lakes” (water inside that isn’t connected to the water around the island). One cell is a square with side length 1. The grid is rectangular, width and height don’t exceed 100. Determine the perimeter of the island.

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206. Reverse Linked List

2018-08-25

Problem description:

Reverse a singly linked list.

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252. Meeting Rooms

2018-08-25

Problem description:

Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],…] (si < ei), determine if a person could attend all meetings.

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34. Find First and Last Position of Element in Sorted Array

2018-08-25

Problem description:

Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value.

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269. Alien Dictionary

2018-08-24

Problem description:

There is a new alien language which uses the latin alphabet. However, the order among letters are unknown to you. You receive a list of non-empty words from the dictionary, where words are sorted lexicographically by the rules of this new language. Derive the order of letters in this language.

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33. Search in Rotated Sorted Array

2018-08-24

Problem description:

Suppose an array sorted in ascending order is rotated at some pivot unknown to you beforehand.

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346. Moving Average from Data Stream

2018-08-23

Problem description:

Given a stream of integers and a window size, calculate the moving average of all integers in the sliding window.

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348. Design Tic-Tac-Toe

2018-08-23

Problem description:

Design a Tic-tac-toe game that is played between two players on a n x n grid.

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785. Is Graph Bipartite?

2018-08-23

Problem description:

Given an undirected graph, return true if and only if it is bipartite.

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211. Add and Search Word - Data structure design

2018-08-23

Problem description:

Design a data structure that supports the following two operations:

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