We are presenting a collection of data structure and algorithm questions and answers for technical interviews for software companies. Questions are collected from real interviews of companies like Microsoft, Amazon, Facebook, Google or Yahoo. Questions are solved and the solutions are discussed in an optimal way which enables you to do a quick preparation for interview. A complete running Java program is added with each problem which you can copy and run in your IDE to understand the solution in a better way. Your feedback is very much appreciated. Please help the site grow by sharing your own problem and solutions or suggestions. Please contact us through feedback@dsalgo.com