1. Explain the React lifecycle methods and how they work.
2. How would you design Google Pay?
3. Describe how you would design a custom data structure based on specific requirements.
4. Do you have experience with vulnerability management?
5. 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: 273 Output: 93 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.