g0601_0700.s0672_bulb_switcher_ii

Class Solution

java.lang.Object

g0601_0700.s0672_bulb_switcher_ii.Solution

public class Solution
extends Object

672 - Bulb Switcher II.

Medium

There is a room with n bulbs labeled from 1 to n that all are turned on initially, and four buttons on the wall. Each of the four buttons has a different functionality where:

• Button 1: Flips the status of all the bulbs.
• Button 2: Flips the status of all the bulbs with even labels (i.e., 2, 4, ...).
• Button 3: Flips the status of all the bulbs with odd labels (i.e., 1, 3, ...).
• Button 4: Flips the status of all the bulbs with a label j = 3k + 1 where k = 0, 1, 2, ... (i.e., 1, 4, 7, 10, ...).

You must make exactly presses button presses in total. For each press, you may pick any of the four buttons to press.

Given the two integers n and presses, return the number of different possible statuses after performing all presses button presses.

Example 1:

Input: n = 1, presses = 1

Output: 2

Explanation: Status can be:

• [off] by pressing button 1

• [on] by pressing button 2

Example 2:

Input: n = 2, presses = 1

Output: 3

Explanation: Status can be:

• [off, off] by pressing button 1

• [on, off] by pressing button 2

• [off, on] by pressing button 3

Example 3:

Input: n = 3, presses = 1

Output: 4

Explanation: Status can be:

• [off, off, off] by pressing button 1

• [off, on, off] by pressing button 2

• [on, off, on] by pressing button 3

• [off, on, on] by pressing button 4

Constraints:

• 1 <= n <= 1000
• 0 <= presses <= 1000

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int	flipLights(int n, int m)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

flipLights

public int flipLights(int n,
                      int m)