Challenge #106: How Long were the Lights On?

[Watermark]

This is an under rated solution. That is flippin brilliant.

[Manonmani]

Here is my Solution

[clmc9601]

My solution

[DeanWest]

Make sure to turn off the lights when you leave the room...

Spoiler

[azure_eller]

Pretty tough but I think this is the first time I've done a weekly challenge without glancing at anyone else's solution. I would be surprised if there isn't an easier way... Guess we'll see after looking at everyone else's submission.

Spoiler

[jonnny2481]

Spoiler

solution attached

[Daje7146]

Here is one solution 

Spoiler

[Toons]

My solution :

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[binuacs]

Spoiler

[JessicaKLarson]