Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V

Question

This is an interview question from google. I am not able to solve it by myself. Can somebody shed some light?

Write a program to print the sequence of keystrokes suc

Answer 1

If N key Strokes are allowed, then the result is N-3.

A's -> N-3

CTRL+A -> Selecting those N Characters :+1

CTRL+C -> Copying those N Characters :+1

Ctrl+V -> Pasting the N Characters. :+1 i.e., (Since we have selected the whole characters using CTRL+A) Replacing these existing N-3 characters with the copied N-3 Characters(which is overriding the same characters) and the result is N-3.