Step 6 of 6
A stack on an array
A stack is last-in, first-out, like a pile of plates: push adds on top, pop removes from the top.
typedef struct {
int items[64];
int top; // number of items
} Stack;
Your turn: implement push (return 0 if full, 1 if ok) and pop (return the top item and remove it; the caller guarantees the stack isn't empty).