Inputs and outputs
Let's start, as always, with a few examples. Running through some inputs helps our brains to intuit some patterns. This may help trigger an insight for a solution.
Let's say we just have this simple binary search
tree:
xxxxxxxxxx
/*
​
5
/ \
3 9
​
*/
OUTPUT
:001 > Cmd/Ctrl-Enter to run, Cmd/Ctrl-/ to comment