Read the stack from bottom to top
Updated
Bottom-to-top is the array writing [bottom, …, top]. Top-to-bottom is the pop order. Say which direction you are printing or you will reverse the stack on paper.
What to focus on
To print bottom-to-top without destroying the stack, walk the backing array 0..size-1, or pop into a helper and push back. Popping as you print is top-to-bottom.
Worked examples
bottom to top
a = [4, 1, 9]- 4 then 1 then 9
Result: 4, 1, 9
top to bottom
a = [4, 1, 9]- 9 then 1 then 4
Result: 9, 1, 4
one item
a = [7]- same both directions
Result: 7
Try it
Write printBoth(a). a is the stack, written [bottom, ..., top]. Print bottom-to-top and top-to-bottom. Label them. A pop-loop prints top-first, not bottom-first. [4, 1, 9] bottom-to-top is 4, 1, 9. Top-to-bottom is 9, 1, 4. [7] is 7 either way.
The stack is non-empty. Values are integers.