1) Problem Solving
Abhi’s Problem Solving Recommendation(one of the best reviews I have ever read and by the way, Abhi is a IIT Madras pass-out)
N.B. -> Massachusetts Institute of Technology’s Recommended Literature for Problem Solving in general, Good Books on Problem Solving, Problem-Solving for the CS Technical Interview, Books by Titu Andreescu
N.B.-> Also, it’s good to be conversant with Elementary/Higher Mathematics topics like Algebra, Number Theory, Geometry, Combinatorics, Graph Theory, Mathematical Logic, Linear Algebra, Multivariable Calculus, Mathematical Programming/Operations Research/Optimization Theory, Probability & Statistics, Game Theory, Auction Theory etc. Some Russian books(translated to English) for the aforementioned branches of Mathematics can be found at Mir Titles.Some other good resources in this respect are AoPS’s Recommended Mathematics Books(in general) , AoPS’s Recommended Olympiad Maths Books and Eric Weisstein’s Mathematics Problem Books Recommendations.
2) Discrete Mathematics
3) Data Structures
A very strongly recommended text to study introductory level Data Structures and Algorithms is Data Structures and Algorithms Made Easy in Java. Very well illustrated and thought provoking solved exercises are there.
Other good Data Structure resources(some are a bit advanced) are –
N.B. -> MSDN C# Data Structure Series, Back to Basics – Generic Data Structures and Algorithms In .NET 2.0, A Heterogeneous Collection Issue , Issue with heterogeneous Tree (the best option to handle this scenario to build a heterogeneous tree dynamically at runtime in .NET 4.0/4.5,seems to be to use List as the type for the children of the tree – agreed that type safety is lost here but if you want type safety then you need to provide the child type for each of the children individually but here you will have to compromise by building the tree statically rather than doing it dynamically – a sample is available here), A Generic Tree Collection , NGenerics – Data Structures and Algorithms for .NET, QuickGraph, Graph Data Structures And Algorithms for .NET
N.B. -> LINQ and Data Structures – LINQ to Tree – A Generic Technique for Querying Tree-like Structures, SkyLink and GraphLINQ
4) Algorithms –
Some awesome resources on Algorithms are –
N.B. -> Algorithmic Puzzles
For Algorithmic problem sets, the following resources are quite good –
5) Cracking Interviews
N.B. -> Google Code Link
N.B. -> Hacking a Google Interview
e) How Would You Move Mount Fuji?