>>12459768Actually, even under the more permissive logic, 694 is the only other allowable answer.
Again, label the conditions (1-5) from top to bottom.
By (1), the code contains 1 number from 291 (which is well-placed) ---(6a)
By (3), the code contains 2 numbers from 463 (which are wrong-placed) ---(6b)
Now if 4 is not included (i.e. 6 and 3 are), then by (2)+(6a) 2 must be included, hence by (1)+(6b) the only possible code is 236, but this contradicts (2). So 4 must be included.
Moreover, 4 cannot be placed first as (3) implies that the code is 436, which contradicts (1). Nor can it be placed in the middle, as (2) implies that 2 is correct but wrong placed (and should be placed last, while the first place is 6 or 3 by (3)), contradicting (1).
So 4 must be in the last place, and by (6a) the code cannot contain 1.
If the code contains 2 (in the first place), then by (3) the code must be 234, but this contradicts (5). So by elimination in (6a), the code contains 9 (in the middle place).
By (6b), the remaining (first) digit is either 6 or 3. Both 694 and 394 are compatible with all the conditions, although only 394 obeys the Gricean implicature of implying no more than necessary.
