I can't understand this problem mean, someone can explain it for me? Why first test and second test have this result?

Test 1:
Den's keys: 0001
            0000

           1st night   2nd night   3rd night  4th night  ... ... ...    All nights

bike's key 0001        0000        0001       0000                      -

bad man    0000        0001        0003       0004                      -

result     no          no          no         no                        no

Test 2:
Den's keys: 0002
            0001

           1st night   2nd night   3rd night  4th night  ... ... ...    All nights

bike's key 0002        0001        0002       0001                      -

bad man    0000        0001        0003       0004                      -

result     no          yes         no         no                        yes

In the first test all nights result is "no". That why in the first test result is no.

Thank you so much! :D

Very Clear answer ! thank you :)

perfect but in line "bad man" , he checks 0002 betwen "0001" and "0003"

Thanks so much

Thank u ...
:)

Thank U!!!