Exercise 8 – Stacks Revisited
(2 marks)
For this lab we will revisit the stack exercise from Lab 1 but with a few changes.
The first entry in the data file contains the initial stack size
The remaining data will consist of a set of lines containing either:
push value
or
pop
with what should be the obvious activity associated with each input – either pushing value onto the
stack or popping the current top value off the stack.
You should start with a stack array of the specified size.
If you attempt to push data onto a full stack you should
Create a new array of twice the current size,
Copy the data from the old stack to the new stack,
Delete the old stack.
Each time this doubling occurs you should output a line to the console of the form:
Stack doubled from old_size to new_size.
If you attempt to pop an empty stack no action should be taken, Do not print an error message.
At the end of the input file you should print a final line of the form:
Stack contains n entries.
This is the only output required.
Example:
If the input file looked like:
2
push 1
push 1
push 1
push 1
push 1
pop
pop
push 1
the output would be:
Stack doubled from 2 to 4.
Stack doubled from 4 to 8.
Stack contains 4 entries.
Note that you do not need to shrink the stack at any time.
As usual, do not use classes or STL.
Submit ex8.ext via moodle as usual where ext is one of c, cpp, java or py.
