Four Keys Keyboard Problem Statement
Imagine you have a special keyboard with four keys:
- Key 1: (A) to print one ‘A’ on screen.
- Key 2: (Ctrl-A) to select the entire screen.
- Key 3: (Ctrl-C) to copy the selection to the buffer.
- Key 4: (Ctrl-V) to paste the buffer's content, appending it after the current content.
Given a positive integer ‘N’, determine the maximum number of 'A's that can be printed on the screen by pressing the keys on this special keyboard ‘N’ times.
Input:
The first line of input contains an integer ‘T’ denoting the number of test cases.
The following ‘T’ lines each contain a positive integer ‘N’, representing the number of times the keys can be pressed on the keyboard.
Output:
For each test case, output a line with the maximum number of ‘A’s that can be printed on the screen.
Example:
Input:
2
7
3
Output:
9
3
Explanation:
In the first test case with N = 7, the optimal sequence is: A, A, A, Ctrl-A, Ctrl-C, Ctrl-V, Ctrl-V. This results in 9 'A's on the screen.
Constraints:
- 1 <= T <= 50
- 1 <= N <= 150
Follow-up:
Try solving the problem in O(N) complexity.
Note:
You do not need to print anything; it has already been taken care of. Just implement the given function.

AnswerBot
4mo
Given a special keyboard with four keys, determine the maximum number of 'A's that can be printed on the screen by pressing the keys 'N' times.
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