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package math;

/**

* Created by gouthamvidyapradhan on 08/09/2017. There is a room with n lights which are turned on

* initially and 4 buttons on the wall. After performing exactly m unknown operations towards

* buttons, you need to return how many different kinds of status of the n lights could be.

*

* <p>Suppose n lights are labeled as number [1, 2, 3 ..., n], function of these 4 buttons are given

* below:

*

* <p>Flip all the lights. Flip lights with even numbers. Flip lights with odd numbers. Flip lights

* with (3k + 1) numbers, k = 0, 1, 2, ...

*

* <p>Example 1: Input: n = 1, m = 1. Output: 2 Explanation: Status can be: [on], [off]

*

* <p>Example 2: Input: n = 2, m = 1. Output: 3 Explanation: Status can be: [on, off], [off, on],

* [off, off]

*

* <p>Example 3: Input: n = 3, m = 1. Output: 4 Explanation: Status can be: [off, on, off], [on,

* off, on], [off, off, off], [off, on, on].

*

* <p>Note: n and m both fit in range [0, 1000].

*/

public class BulbSwitcherII {

public static void main(String[] args) throws Exception {

System.out.println(new BulbSwitcherII().flipLights(1, 1000));

}

public int flipLights(int n, int m) {

if (n == 0 || m == 0) return 1;

if (n == 1 && m >= 1) return 2;

if (n == 2) {

if (m == 1) return 3;

if (m >= 2) return 4;

} else if (n >= 3) {

if (m == 1) return 4;

if (m == 2) return 7;

}

return 8;

}

}