I asked this question to a friend here at Duke and this was his answer,
"The answer to your question depends largely on what field you want to pursue within computer science.
Enterprise jobs working on the backend will typically require extensive fluency with databases and some of the more heavy duty object oriented languages. In that situation, SQL (or something like MongoDB if you would like to pursue a more new-age NoSQL solution) on top of Java and C# should be wonderful introductions. Higher level object oriented languages can teach you many of the necessary skills you will need to know when it comes to architecting the general flow of large applications and supplementary resources like Git will introduce you to the code-sharing concepts that are fundamental to large design teams.
C and C++ are essential to any low-level design work such as coding in drivers or working in areas where memory cannot be taken for granted.
Finally, python is a perennial favorite due to the sheer flexibility and extensive documentation it wields while still being much more concise than competitors like java.
In terms of just learning the concepts behind computer science, any language will do. Most are analogues of C and inevitably have similar syntax and are simple to learn once a basic understanding of the fundamentals of computer science are learned by mastering any one language.
Above all, it is more important to grasp things like how to avoid spaghetti code and making your code efficient than it is to learn every single language. As mentioned before, tools like SQL and Git can greatly compliment your learning experience as they allow you to work with real data and solutions from other developers respectively."
This is quite in-depth but I hope it helps you out!