Introduce

Source：How can I learn algorithms and data structures from scratch? - Quora

It feels like this site has a foreign flavor of Zhihu

Plan

Day −∞−∞ to 0: Stick to a programming language like C or C++. Make sure that you are comfortable with pointers/objects.

对象和指针理解

Day 1: Understand the concept of Algorithmic complexity^[1]. Skip the theory for now, but for every piece of code you write, you should be able to derive both time and space complexity.

时间复杂度和空间复杂度了解，可以估算算法的时间和空间复杂度，理论部分可以跳过

Day 2 - 10: Let’s start with some simple data structures,

Arrays
Linked Lists
Strings
Stacks
Queues

Understand their basic operations (insert, delete, search, traversal) and their complexity - Big-O Algorithm Complexity Cheat Sheet^[2], and code them all.

理解常见线性和非线性数据结构的增删改查的细节。

Day 11 - 25: Let’s now learn some simple algorithms,

Sorting - Insertion sort^[3], Merge sort^[4], Quick sort^[5], Heap sort^[6], Bucket sort^[7], Counting sort^[8], Radix sort^[9], External sorting^[10]
Search - Linear search^[11], Binary Search^[12] (along with its variants).
Prime Numbers - Sieve of Eratosthenes^[13], Primality test^[14]
Strings - String searching^[15], LCS^[16], Palindrome detection^[17]
Miscellaneous - Euclidean algorithm^[18], Matrix multiplication^[19], Fibonacci Numbers^[20], Pascal's Triangle^[21], Max Subarray problem^[22]

归纳：

常见排序算法

搜索算法

素数

字符串查找

杂七杂八算法

Day 26 - 50: Once you are comfortable with everything above, start doing problems from,

Cracking the Coding Interview^[23]
Elements of Programming Interviews^[24]
Programming Interviews Exposed: Secrets to Landing Your Next Job^[25]
GeeksforGeeks^[26]
HackerRank^[27]
InterviewBit^[28]

面试常考算法，然后需要反复练习常见数据结构的相关算法

Stick to chapters of arrays, linked lists, strings, stacks, queues and complexity.

Day 51 - 60: Let’s learn some non-linear data structures,

非线性结构算法学习

Tree
Binary Tree, Binary Search Tree - Tree traversals^[29], Lowest common ancestor^[30], Depth, Height & Diameter^[31], Finding k-th smallest element^[32]
Heaps
Hash table - 4 sum problem^[33], Checking if sudoku solution is valid^[34]
Graph - Breadth-first search^[35], Depth-first search^[36], Topological sorting^[37], Minimum spanning tree^[38], Shortest path problem^[39],

二叉树、二叉树查找哈希表垃圾回收算法。图

Day 61- 90: Refer to the previous resources and start doing problems from trees, hash tables, heaps and graphs.

参考之前的练习，使用非线性结构的思维模式重做一遍。

Day 91 - 100: Understand Computational complexity theory^[40] and NP-completeness^[41], Knapsack problem^[42], Travelling salesman problem^[43], SAT problem^[44] and so on.

理解计算机复杂性理论，NP，SAT，TSP、动态规划等。

Day 101 - ∞∞: You are now better than most of the CS undergrads. Keep revising the above topics and start competitive programming! Good luck!

你现在比大多数的CS本科生都要好。继续复习上述题目，并开始竞争性的编程! 祝您好运!

参考资料

[1]

en.wikipedia.org: https://en.wikipedia.org/wiki/Algorithmic_complexity

[2]

bigocheatsheet.com: http://bigocheatsheet.com/

[3]

en.wikipedia.org: https://en.wikipedia.org/wiki/Insertion_sort

[4]

en.wikipedia.org: https://en.wikipedia.org/wiki/Merge_sort

[5]

en.wikipedia.org: https://en.wikipedia.org/wiki/Quicksort

[6]

en.wikipedia.org: https://en.wikipedia.org/wiki/Heapsort

[7]

en.wikipedia.org: https://en.wikipedia.org/wiki/Bucket_sort

[8]

en.wikipedia.org: https://en.wikipedia.org/wiki/Counting_sort

[9]

en.wikipedia.org: https://en.wikipedia.org/wiki/Radix_sort

[10]

en.wikipedia.org: https://en.wikipedia.org/wiki/External_sorting

[11]

en.wikipedia.org: https://en.wikipedia.org/wiki/Linear_search

[12]

www.topcoder.com: https://www.topcoder.com/community/data-science/data-science-tutorials/binary-search/

[13]

en.wikipedia.org: https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes

[14]

en.wikipedia.org: https://en.wikipedia.org/wiki/Primality_test

[15]

en.wikipedia.org: https://en.wikipedia.org/wiki/String_searching_algorithm

[16]

en.wikipedia.org: https://en.wikipedia.org/wiki/Longest_common_subsequence_problem

[17]

www.rosettacode.org: https://www.rosettacode.org/wiki/Palindrome_detection

[18]

en.wikipedia.org: https://en.wikipedia.org/wiki/Euclidean_algorithm

[19]

en.wikipedia.org: https://en.wikipedia.org/wiki/Matrix_multiplication

[20]

en.wikibooks.org: https://en.wikibooks.org/wiki/Algorithm_Implementation/Mathematics/Fibonacci_Number_Program

[21]

www.geeksforgeeks.org: http://www.geeksforgeeks.org/pascal-triangle/

[22]

en.wikipedia.org: https://en.wikipedia.org/wiki/Maximum_subarray_problem

[23]

www.amazon.com: https://www.amazon.com/Cracking-Coding-Interview-Programming-Questions/dp/0984782850

[24]

www.amazon.com: https://www.amazon.com/Elements-Programming-Interviews-Insiders-Guide/dp/1479274836

[25]

www.amazon.com: https://www.amazon.com/Programming-Interviews-Exposed-Secrets-Landing/dp/1118261364

[26]

www.practice.geeksforgeeks.org: http://www.practice.geeksforgeeks.org/

[27]

www.hackerrank.com: https://www.hackerrank.com/

[28]

www.interviewbit.com: https://www.interviewbit.com/invite/afaf

[29]

en.wikipedia.org: https://en.wikipedia.org/wiki/Tree_traversal

[30]

en.wikipedia.org: https://en.wikipedia.org/wiki/Lowest_common_ancestor

[31]

stackoverflow.com: http://stackoverflow.com/questions/2603692/what-is-the-difference-between-tree-depth-and-height

[32]

www.geeksforgeeks.org: http://www.geeksforgeeks.org/find-k-th-smallest-element-in-bst-order-statistics-in-bst/

[33]

www.sigmainfy.com: http://www.sigmainfy.com/blog/4sum-problem-analysis-different-time-complexity.html

[34]

stackoverflow.com: http://stackoverflow.com/questions/5484629/check-if-sudoku-solution-is-valid

[35]

en.wikipedia.org: https://en.wikipedia.org/wiki/Breadth-first_search

[36]

en.wikipedia.org: https://en.wikipedia.org/wiki/Depth-first_search

[37]

en.wikipedia.org: https://en.wikipedia.org/wiki/Topological_sorting

[38]

en.wikipedia.org: https://en.wikipedia.org/wiki/Minimum_spanning_tree

[39]

en.wikipedia.org: https://en.wikipedia.org/wiki/Shortest_path_problem

[40]

en.wikipedia.org: https://en.wikipedia.org/wiki/Computational_complexity_theory

[41]

en.wikipedia.org: https://en.wikipedia.org/wiki/NP-completeness

[42]

en.wikipedia.org: https://en.wikipedia.org/wiki/Knapsack_problem

[43]

en.wikipedia.org: https://en.wikipedia.org/wiki/Travelling_salesman_problem

[44]

en.wikipedia.org: https://en.wikipedia.org/wiki/Boolean_satisfiability_problem