I did the first three in this series of online Coursera courses from UC San Diego and I thought they were quite good: https://www.coursera.org/specializations/d

I did the first three in this series of online Coursera courses from UC San Diego and I thought they were quite good: https://www.coursera.org/specializations/data-structures-algorithms https://www.coursera.org/specializations/data-structures-alg... You end up implementing the algorithms and data structures yourself in your language of choice, which I find is a good way to learn.