Dynamic Stack

easy

1. You are given the code of our CustomStack class which mimics the java.util.Stack class.
2. Here is the list of functions that are written in the class...
    2.1. push -&gt; Accepts new data if there is space available in the underlying array or 
     print "Stack overflow" otherwise
     2.2. pop -&gt; Removes and returns last data if available or print "Stack underflow" 
     otherwise and returns -1
     2.3. top -&gt; Return last data if available or print "Stack underflow" otherwise and 
      returns -1
     2.4. size -&gt; Returns the number of elements available in the stack
     2.5. display -&gt; Print the elements of stack in LIFO manner (space-separated) 
     ending with a line-break.
3. Input and Output are managed for you.
4. You are required to change the body of push function to accept the element even when the data array is completely full. In that case, you are required to reallocate the data array (to twice it's size). You should not print "Stack overflow" ever.

Input Format

Input is managed for you

Output Format

Output is managed for you

Constraints

None

Notice

Try First, Check Solution later

1. You should first read the question and watch the question video.
2. Think of a solution approach, then try and submit the question on editor tab.
3. We strongly advise you to watch the solution video for prescribed approach.

Example

Input

5
push 10
display
push 20
display
push 30
display
push 40
display
push 50
display
push 60
display
top
pop
display
top
pop
display
top
pop
display
top
pop
display
top
pop
display
top
pop
quit

Output

10 
20 10 
30 20 10 
40 30 20 10 
50 40 30 20 10 
60 50 40 30 20 10 
60
60
50 40 30 20 10 
50
50
40 30 20 10 
40
40
30 20 10 
30
30
20 10 
20
20
10 
10
10

Normal Stack

Normal Queue