Lists:
1. GeesForGeeks: http://www.geeksforgeeks.org/
2. LeetCode: https://oj.leetcode.com/
3.Visualgo: http://visualgo.net/ (including some dynamic animations)
4.Wikiwand: http://www.wikiwand.com/en/
book:
<<Introduction to Algorithm >>
原文：http://www.cnblogs.com/freecodeX/p/4233345.html