Water, an overflowing container, a dry fabric, and a protocol that removes songs from the playlist relatively than provides them.

Alice and Bob have buckets that take a most of 4 items. They have a container that may maintain a most of 4 items. They resolve if every track will keep on the playlist by including water from the buckets to the container. A hate vote is 4 items. Tolerate is 3. Like is 2. And love is 1.

An even bigger container prevents Alice and Bob from inferring the opposite’s preferences based mostly on water quantity.

Alice and Bob fill their buckets in response to their tastes, then in separate rooms, dump them into funnels that result in the overflow container. If there’s any overflow, the track is faraway from the playlist.

A dry fabric is positioned below the container because the indicator.

In numbers:

They are doing a easy weighted vote. A hate vote is 4 and a love vote is 1, 5 complete. This will overflow the container and take away the track. A tolerate vote is 3, and with a love vote of 1, it totals 4 and the track stays on the record.

Shared like and love votes turn out to be identified precisely, however combos of hate, tolerate, and like votes are all the time obscured. If you need to additionally obscure like and love mixture votes

then you may make the container opaque and have a drain plug that may be pulled with out trying in.

If Alice and Bob had been extra trustworthy

they might use syringes and a a lot smaller overflow container, after which merely look away in the meanwhile they vote. They might additionally use a small little bit of tissue paper as a substitute of a fabric.

Instead of a dry fabric, you possibly can add obscurity through the use of a scale.

All water overflow is captured by one other opaque container which sits on a scale that merely lights up when there’s any weight added. Light on means take away from record, mild off means it stays. They pull the plugs to empty the containers then begin once more.