How do you score a multi team swim meet?

It depends on the type of meet.-

At a high school swim meet, a single team will get a number of different scores, a different one against each other team that is there. It is scored as though there were only two teams. For example- team A gets first in an event, B gets second, and C gets third. In the meet between teams B and C, B will get the points for first and B will get the points for second because team A doesn't exist at their dual meet. In the end, team A could could win against team B and lose to team C, but they will get first out of two and second out of two, not second out of three.

Club swim meets are a bit easier- If team A gets first in an event, B gets second, and C gets third, A gets points for first, B gets points for second, and C gets points for third, so it would be second out of three, not first out of two and second out of two.

~Hope I helped~