Program Creek

Source: Programming Creek

This site summarizes the common subjects in coding interviews, including :

1. String/Array/Matrix,
2. Linked List,
3. Tree,
4. Heap,
5. Graph,
6. Sorting,
7. Dynamic Programming,
8. Bit Manipulation,
9. Combinations and Permutations, and
10. Math.

Though the problems mentioned into one cateogry, it may not always be the case because the problem may belong to multiple categories!