One person comes up to another person beside his bike. "Can I use your bike?" he asks. The person by the bike replies, "Only if you figure out the combination to my bike lock, which is made up of 4 different numbers from 1 through 8. You can guess 3 numbers."
He guessed 1235, 4721, and 3862. All three were answered with "One number in the combination is in the wrong place, and another is in the right place. The other two aren't in the combination."
The guesser was puzzled and asked "Is the number divisible by 7?" The person with the bike answered this question and after thinking for a while, the guesser told him the combination. What is the combination?
(In reply to Not to belabor this, but.....
As fwaff pointed out, he limited the solution and 'brute forced' it as well. Kudos to him for doing it a different way, and not relying on a program.
I sincerely wish you had not missed the only number that fit the criteria that was also divisible by seven (namely 2765).
If you had found it, it would have saved us
(1) your desire to change the problem,
(2) your ranting about computer programs, and
(3) apparent dismissal of the solution(s) that solved the problem correctly before you did, which seems to be what is driving your comments