Six statements about a hidden 4-digit code.
Digits are 1–6 and can repeat. Exactly one statement is a lie. Two of them contradict each other — find that pair first.
Rule out digits — tap to cross off
Saved on this device
Find the liar. Then find the code.
How to play
A hidden 4-digit code, digits 1 to 6, repeats allowed. You get statements
about it — and exactly one is a lie. Crack it in three attempts, using logic alone.
Start here. Every puzzle contains two statements that cannot both be
true. Find that pair and you are most of the way home.
Because only one statement lies, the liar has to be one of those two —
which means every other statement is true:
3. Position 1 is a 4.
5. Position 1 is a 2. Both can't be true. So the liar is 3 or 5, and statements 1, 2, 4 and 6 are all true —
use those to pin the code down, then see which of 3 or 5 it breaks.
Tap a statement to mark it up as you think:
×struck through — you suspect this one is the lie
✓ticked — you've confirmed it's true
Stuck? Open the scratchpad. The SCRATCHPAD button under the statements
gives you a notepad and a grid for crossing off digits you have ruled out:
P1123456
P2123456
Everything you write is kept on your device until the next case.
Each guess tells you two things:
▮how many positions are correct
✗how many statements your guess breaks
The right answer breaks exactly one statement — because there is exactly one lie.
Breaking zero means your code is too perfect to be right.