I took the Dasgupta's algorithms class at UCSD a couple years ago. I don't know the legal status of the PDF there, exactly, but he gave the link out to the class and almost everyone in the class used it instead of a physical textbook.
I thought the text (and class) was pretty good, although I'm sure being in the class helped. You should definitely have some experience with basic data structures, discrete math and graph theory before diving into it.
Comments
I took the Dasgupta's algorithms class at UCSD a couple years ago. I don't know the legal status of the PDF there, exactly, but he gave the link out to the class and almost everyone in the class used it instead of a physical textbook.
I thought the text (and class) was pretty good, although I'm sure being in the class helped. You should definitely have some experience with basic data structures, discrete math and graph theory before diving into it.