Redis is an open source, advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets.
http://redis.io/
There are many Redis client as different language binding available:
http://redis.io/clients
For C++, there is a client library recommanded by official named redis-cpp-client but too bad it can neither build nor run on Windows platform.
This project is a little tweek on the official C++ client...