A master thief leaves a safe behind with a note: 'The combination is a 4-digit number where the first digit is the number of zeros in the code, the second is the number of ones, the third is the number of twos, and the fourth is the number of threes.' What is the 4-digit combination?
1210
Testing 1210: It contains one '0', two '1's, one '2', and zero '3's. Matching the digit positions to these counts gives 1 (zeros), 2 (ones), 1 (twos), 0 (threes) -> 1210.
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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