m*n platform

• how many ways can you take to walk from top left to bottom right by stepping right or down every time?

max gold mine value

• n gold mines, every one has different value and miners to dig, what's the max value can you get with m miners?

binary sort tree

• build a binary sort tree with an unsorted array
• transfer to a balanced btree? ref avl tree
• output an btree using one way of pre-order, in-order or post-order
• find a node whose value is just bigger than the specified number

avl tree

• balanced binary sort tree: difference in height is less than 2 between left and right node

hanoi tower

• there're three towers(called A,B and C) and n different circles whose redius is growing with serial. Move these circles from A to C keeping the serial no in A. One circle every time, and the large circle cannot be above the small ones.