A Beijing park started using facial recognition scanners to save toilet paper and stop thieves. They scan people's face and give them 60 cm of toilet paper. You must wait for nine minutes if you want extra paper. Some park visitors took too much toilet paper. The park put up posters asking visitors to use less toilet paper.

There is a surprise. The scanners are now a tourist attraction. Visitors are coming to see them. Videos of people using them have gone viral on the Internet. Staff help people who need more toilet paper. A social media user said: "This is a really good idea." The amount of toilet paper used is down by 20%.