Steem Riddle of the Week #3: Doppledanger Robots - Solution Revealed

Solution to Riddle #3: Doppledanger Robots

For those who missed it the full riddle is stated here: https://steemit.com/life/@droopy/steem-riddle-of-the-week-3-alternating-truth-prize-for-first-correct-answer. Warning, spoilers are below! If you'd like to take a crack at the riddle on your own before seeing the solution, do not scroll down!

Finally, @mtness was very close to solving the riddle but did not quite get it, so I am awarding him half of the prize!

Be sure to follow me to get notified when the next riddle comes out, most likely tomorrow!

The Riddle
There are 5 robots that appear completely identical, however one of them is good one the other 4 are broken.

You must pick a single robot and ask it two questions. After that you must correctly point to the good robot.

The good robot will answer both questions honestly. The broken robots will all answer one question honestly and lie to one question. You don't know whether they will lie when answering the first question and answer the second honestly, or lie when answering the second question and answer the first truthfully.

What questions should you ask and what is your strategy? Your strategy must guarantee that you always pick the correct robot after asking your two questions in all possible cases.

1. All of the robots know which robots are good and which are not.
2. You are not limited to yes/no questions. You can ask something like "point to the good robot"
3. If you ask a non-yes/no question and the robot lies it may use any lie, but it will never tell the truth. Your strategy must work regardless of what lie it tells.

The Solution
Pick a random robot. First ask it "Are you the good robot?" If it says yes, then ask it to point to the good robot. If it says no, then ask it to point to a robot that is bad. Pick whatever robot it points to after the second question. Why does this work?

Well, there are 3 cases. If the random robot that we picked is the good robot, it will say yes to the first question and then point to itself, as it is always honest.

If the random robot that we picked is broken, and lies first then tells the truth, it will say yes to the first question. Then it will have to answer the second question honestly by pointing to the good robot.

Finally, if the random robot that we picked is broken and tells the truth first, and then lies, it will say no to the first question. When we ask it to point to a bad robot as our second question, it must point to a robot that is not bad in order to lie, so it will point to the one good robot.

In all 3 cases, we'll succeed.

Don't forget to check out last weeks riddle if you missed it

Last weeks riddle is here : https://steemit.com/life/@droopy/steem-riddle-of-the-week-2-flipping-cards-prize-doubled
Answer to last weeks riddle: https://steemit.com/life/@droopy/steem-riddle-of-the-week-2-flipping-cards-answer-revealed