In a digital vault, a password consists of a four-digit number where the first digit equals the number of zeros in the entire code, the second digit equals the number of ones, the third equals the number of twos, and the fourth equals the number of threes. What is the code?
1210
In the number 1210: there is 1 zero (matching the first digit '1'), there are 2 ones (matching the second digit '2'), there is 1 two (matching the third digit '1'), and there are 0 threes (matching the fourth digit '0').
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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