Visual representation of Algorithm/Data Structures

1. http://qiao.github.io/PathFinding.js/visual/
2. http://visualgo.net/
3. http://www.codeskulptor.org/

Data Structures and Algorithms

1. http://theshayna.com/data-structures-and-algorithms-tutorials/
2. http://www.rookieslab.com/
3. http://www.iarcs.org.in/inoi/online-study-material/
4. https://algo.is/competitive-programming-course/ — Competitive Programming Course
5. http://20bits.com/article/introduction-to-dynamic-programming — Get started with DP
6. http://bigocheatsheet.com/ — Know the Complexities
7. http://kaidul.com/algorithm-data-structure-code-library/
8. http://notes.tweakblogs.net/blog/9835/fenwick-trees-demystified.html — Fenwick trees Demystified
9. http://codeforces.com/blog/entry/15729 — Data Structures tutorial
10. http://www.comp.nus.edu.sg/~stevenha/methodstosolve.html?uid=625047&showAC=1 — Checklist for UVA
11. http://algorithms.tutorialhorizon.com/
12. http://informatics.mccme.ru/

Online Encyclopaedia for IntegerSeqeunces

1. https://oeis.org/

Blogs

1. IIT KANPUR — ACM BLOG(http://www.cse.iitk.ac.in/users/aca/index.html)
2. http://sportprogramming.blogspot.in/2014/07/getting-started-with-sport-of.html — Try to Implement every problem given in this blog
3. http://freedomofkeima.com/blog/posts/brush-up-your-programming-skill Wiki Pages: http://wcipeg.com/wiki/Special:AllPages
4. http://www.vexorian.com/ — Try to read every entry of this blog, It's quite good.
5. http://blog.anudeep2011.com/ — Segment tree, Heavy light Decomposition explained.
6. http://zobayer.blogspot.in/2015/06/dynamic-programming-dp-problems-from.html — Find DP Problems from SPOJ
7. https://kartikkukreja.wordpress.com/ — One of the most interesting blogs, I have ever seen- consist many AI related problems and CP tutorials with reviews of courses. Must read.
8. http://fusharblog.com/ — Find how to solve linear recurrences. Must read for Matrix Exponentiations.
9. http://blog.hackerearth.com/
10. http://contest-wiki.csc.kth.se/index.php/How_to_get_better%3F
11. https://www.quora.com/What-were-the-pointers-given-by-Ajay-Somani-to-Nikhil-Garg-regarding-preparation-for-ICPC
12. https://www.quora.com/How-did-Anudeep-Nekkanti-become-so-good-at-competitive-programming
13. https://www.topcoder.com/community/stories/
14. https://www.hackerearth.com/ama/i-am-lalit-kundu-algorithmist-programmer-acm-icpc-15-kgp-winner-ask-me-anything/
15. http://contest-wiki.csc.kth.se/index.php/Team_strategy — Team Strategy
16. https://tp-iiita.quora.com/

Mathematics

1. http://geomalgorithms.com/math.html#Coordinate-Systems
2. http://neerc.ifmo.ru/wiki/index.php?title=%D0%94%D0%B8%D1%81%D0%BA%D1%80%D0%B5%D1%82%D0%BD%D0%B0%D1%8F_%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%2C_%D0%B0%D0%BB%D0%B3%D0%BE%D1%80%D0%B8%D1%82%D0%BC%D1%8B_%D0%B8_%D1%81%D1%82%D1%80%D1%83%D0%BA%D1%82%D1%83%D1%80%D1%8B_%D0%B4%D0%B0%D0%BD%D0%BD%D1%8B%D1%85
3. http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibpuzzles.html — Fibonacci Quest Solved
4. http://e-maxx.ru/algo/

Search Engine For Computer Scientists: https://censys.io/

Awesome Resources List

1. https://docs.google.com/document/d/1PTu3MLbyyMkMUboKO6AmdIJ02InFmtZDT2e3qbJOlKA/edit
2. http://codeforces.com/blog/entry/23054