I was just about to call an end to my day and go to bed when Rob sent me an email and told me to take a look. I opened it a discovered a puzzle. Well. A brain teaser I guess you could call it. I like puzzles. Unfortunately I am not good at walking away from them. So there I sat needing to go to the washroom and wanting to go to bed but unwilling to leave until I found the answer.
Below is the email he sent can you answer the question?
This problem can be solved by pre-school children in 5-10 minutes, by programer – in 1 hour, by people with higher education … well, check it yourself!
8809=6
7111=0
2172=0
6666=4
1111=0
3213=0
7662=2
9313=1
0000=4
2222=0
3333=0
5555=0
8193=3
8096=5
7777=0
9999=4
7756=1
6855=3
9881=5
5531=0
2581=?