when pure loop doesn't work out

10-01

Btree traversal

10-01

construct a self balanced BStree

09-24

construct BTree from pre/in/post-order input

09-19

construct BTree from breadth-order input

09-19

print combinatorics

09-19

scrabmle string

09-11

how dynamic programming works

09-04

how recursive works with passing reference variables

08-29

how backtracks work

08-29