R Leigh wrote:criticized the book over too much of complex maths involved

Complex numbers are rarely used in analysis of algorithms, in fact most of it is done using integers and some fractions, so the irrational numbers are rarely used.

Or did you mean hard? Most of the math used in analysis of algorithms is calculus (limits) and some work with infinite series. Its solidly college level math. If you didn't do well in other college level math, you're not going to be happy.

When I was in grad school, we used Sarah Baase's Computer Algorithms: Introduction to Design and Analysis, third edition, co-authored with Allen Van Gelder, Addison-Wesley, 2000.