Pop and Peek on an Array Stack

The array stack can already push and display itself. The two ways of reading the top item are missing, and they differ in exactly one way: one of them moves top and one leaves it alone.

Requirements:
1. Complete pop() so it returns the top value and removes it.
2. Complete peek() so it returns the top value and leaves the stack untouched.
3. Both return -1 on an empty stack. Never print from inside the class.

Do NOT write a main method.

Expected Output:

30↵
30↵
30↵
20↵
Stack: 10↵

= newline. The output ends with a newline — print one after the last line.

Hints4 available

Topics:

Data Structures & AlgorithmsStacks

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