The stack is used while evaluating arithmetic expressions so that a statement such as:

2 + 3 -> x;actually takes place in four steps, thus:

(1) Put 2 on the stack (2) Put 3 on the stack (3) Do the addition, that is remove the top two items on the stack (ie 2 and 3) and replace them by their sum (ie 5) (4) Remove the top item from the stack (ie 5) and put it in the variable X.A more complicated example, such as:

2 + 3 * 4 - 5 =>takes place in EIGHT steps, which are left as an exercise for the reader to describe, some of which are:

(4) Do a multiplication (5) Do an addition (7) Do a subtraction (8) Print the contents of the stack

Fri Jan 2 03:17:44 GMT 1998