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
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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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