PROCEDURE ADD(ITEM, STACK, N, TOP)
[Inserts ‘item’ into the ‘stack’ of maximum size ‘n’, top is the number of elements currently in ‘stack’.]

1. [Overflow ?]

if (TOP >= N)
write Stack is full.
return.

2. [Increment top]

top <-- top + 1

3. [Insert Element]

stack [top] <-- item.

4. [FINISH]
return.