I have owned 11 bikes. This is how they were stolen

This article is from January 2023 but saw this excerpt making the rounds on twitter about computer scientists trying to teach cops binary search

> Bike 8 was stolen from a station cycle rack, where I had parked it directly beneath a camera. This time, I thought, we have them. Triumphantly I went to the police. “Look!” I said. “You will be able to see them.” They refused to look at the footage unless I could narrow it down to a window shorter than a few hours. This is, I discovered, a common response.

> Afterwards I found a chatroom thread among Cambridge computer scientists, one of whom had also been told that unless he could pin down the moment of theft no one would look at the footage. He said he had tried to explain sorting algorithms to police — he was a computer scientist, after all.

> You don’t watch the whole thing, he said. You use a binary search. You fast forward to halfway, see if the bike is there and, if it is, zoom to three quarters of the way through. But if it wasn’t there at the halfway mark, you rewind to a quarter of the way through. It’s very quick. In fact, he had pointed out, if the CCTV footage stretched back to the dawn of humanity it would probably have only taken an hour to find the moment of theft. This argument didn’t go down well.

> I made a (slightly more diplomatic) nuisance of myself and they eventually looked at the footage. The policewoman I dealt with was lovely about it, but in the end the image wasn’t clear. Maybe they were right not to bother.