There are n bulbs in a circle, each bulb has one switch associated with it, on operating the switch, it toggles the state of the corresponding bulb as well as two bulbs adjacent to that one. Given all bulbs are in off state initially, give a plan to turn all bulbs on finally.

Note: n >= 1.

• There is a simpler solution, if n is a multiple of 3 do it as done by author, first 1 the 1+3=4 then 4+3=7 and so on upto n/3 the number of steps taken will be n/3
  otherwise, start from bulb number 1 and keep switching it on till the last bulb i.e switch on 1, then 2 then 3 and so on upto n, it will take n steps and all bulbs will be in the on state finally
  (The solution given by author is also taking n steps in both the cases n=7 and n=8 if you observe closely)
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