If you're seriously considering majoring in CS, I would highly recommend this book (aside from any standard programming language book if you don't know how to program yet) to give you a watered down prep for what you will thoroughly analyze in your ~junior year in an Algorithms course
Algorithms is probably the standard weed out course for computer science where you will need to know how to evaluate and prove the runtime and memory requirements of many different algorithms, and know if certain problems are NP complete. I think that's the first time dynamic programming is also explored in detail.
Computer science is all happy go lucky up until this course. Up to this point, it's about learning the syntax of a few different programming languages and the strengths/weaknesses of each language (spoilers: Java sucks). And then also standard software engineering stuff.
After or around the time you're concerned about Algorithms, you'll also be introduced to the second weed out class that focuses on learning Assembly or some other very low level language where you'll most likely have to program a microcontroller. This is the next class after Digital Logic type course.
Source: I have a bachelors (CS), masters (CSE), and PhD (CS-related research area) and am personally familiar with the CS curriculum of the following schools: Alabama, Georgia, Notre Dame, USC, UCSD, and some of what they teach at Maryland
I'm starting CS at Georgia, what do you think of their program?