There is an equiprobability of winning/losing/draw. Your code is erroneous.
You do a +1 to the random number you generate giving you 1, 2, 3. You then use that number to access an array with indexes [0, 1, 2]. You end with an undefined which screws your results.
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Is it actually a 1/3 chance of winning though? Is that including a draw as a win?
I've tried coding it up here:
https://gist.github.com/andyhmltn/5c8c5734fe894db5aa02
Baring in mind it was a rushed 5 minute bodge-job so it could be wrong but there seems to be a massive skew towards draws
After more tests with this code it seems there's an 11% chance of winning if it's random. Baring in mind javascripts RNG
There is an equiprobability of winning/losing/draw. Your code is erroneous. You do a +1 to the random number you generate giving you 1, 2, 3. You then use that number to access an array with indexes [0, 1, 2]. You end with an undefined which screws your results.
Well if that was the case, then one result would always have 0. The indexes are used to find what something wins against