Evan's Blog | Algorithms

House Robber

Leetcode-198

House Robber Question You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of th...

Posted by Evan on December 14, 2017

Reverse Integer

Leetcode-7

Reverse Integer Question Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 120 Output: 21 No...

Posted by Evan on November 22, 2017

Maximum Length of Repeated Subarray

Leetcode-718

Maximum Length of Repeated Subarray Question Given two integer arrays A and B, return the maximum length of an subarray that appears in both arrays. Example 1: Input: A: [1,2,3,2,1] B: [3,2,1,4,7]...

Posted by Evan on November 18, 2017

Is Subsequence

Leetcode-392

Is Subsequence Question Given a string s and a string t, check if s is subsequence of t. You may assume that there is only lower case English letters in both s and t. t is potentially a very long ...

Posted by Evan on November 10, 2017

Predict the Winner

Leetcode-486

Predict the Winner Question Given an array of scores that are non-negative integers. Player 1 picks one of the numbers from either end of the array followed by the player 2 and then player 1 and so...

Posted by Evan on November 2, 2017

Merge Two Sorted Lists

Leetcode-21

Merge Two Sorted Lists Question Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists. Answer 这道题比较简单，就是归并的链表...

Posted by Evan on October 22, 2017

Letter Combinations of a Phone Number

Leetcode-17

Letter Combinations of a Phone Number Question Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telep...

Posted by Evan on October 17, 2017

Palindromic Substrings

Leetcode-647

Palindromic Substrings Question Given a string, your task is to count how many palindromic substrings in this string. The substrings with different start indexes or end indexes are counted as diff...

Posted by Evan on October 10, 2017

House Robber II

Leetcode-213

House Robber II Question Note: This is an extension of House Robber. After robbing those houses on that street, the thief has found himself a new place for his thievery so that he will not get too...

Posted by Evan on October 1, 2017

Search a 2D Matrix II

Leetcode-240

Search a 2D Matrix II Question Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties: Integers in each row are sorted in ascending ...

Posted by Evan on September 17, 2017

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