672. Bulb Switcher II
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.
Suppose n
lights are labeled as number [1, 2, 3 ..., n], function of these 4 buttons are given below:
- Flip all the lights.
- Flip lights with even numbers.
- Flip lights with odd numbers.
- Flip lights with (3k + 1) numbers, k = 0, 1, 2, ...
Example 1:
Input: n = 1, m = 1.
Output: 2
Explanation: Status can be: [on], [off]
Example 2:
Input: n = 2, m = 1.
Output: 3
Explanation: Status can be: [on, off], [off, on], [off, off]
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].
Note: n
and m
both fit in range [0, 1000].
# @lc code=start
using LeetCode
function flip_lights(n::Int, m::Int)
n = min(n, 3)
m == 0 && return 1
m == 1 && return [2, 3, 4][n]
m == 2 && return [2, 4, 7][n]
return [2, 4, 8][n]
end
# @lc code=end
flip_lights (generic function with 1 method)
This page was generated using DemoCards.jl and Literate.jl.