Escape RoomRiddle #1411
A three-digit lock comes with four notes. 792: two digits are right and in the right spots. 837: one digit is right but in the wrong spot. 832: nothing is right. 691: one digit is right and in the right spot, and one is right but in the wrong spot. What's the code?
Hint: 832 clears out three digits at once. Then ask which two of 7, 9 and 2 can be the right ones.
Answer
796
832 rules out 8, 3 and 2. So 837 means 7 is in the code but not last. In 792 the 2 is out, so 7 and 9 are both right and placed: 7 first, 9 second. In 691, 9 is the placed digit, so 6 or 1 is in the code but misplaced. Only the last spot is open, and 1 is already last in 691, so it must be 6: 796. A brute-force check confirms it is the only answer.
Did you get it?
Nice work. On to the next one.
Got you this time. Try the next one.
