It really depends on what you're aiming for. - pure mathematical stuff, graphs and such, you can skip programming - making algorithms/protocols/etc by simple

It really depends on what you're aiming for. - pure mathematical stuff, graphs and such, you can skip programming - making algorithms/protocols/etc by simple models require to understand what a computer can do, etc so learn at least Python - making new architectures, efficient functions (like for crypto), go to C. I am suggesting Python, because it is probably the simplest programming language to learn. I'm not saying that learning Python when you do purely theoretical stuff is useless, just that you can skip it and still work. Event if you do no CS-related things, programming is useful. tl;dr: go for Python, unless you need to now the specific workings of a computer