What is the ruling on a ritually impure garment touching a ritually pure garment?

If something pure touches something impure and one of them is wet, the pure item becomes impure. So, if pure clothes touch impure clothes and one of them is wet, they become impure; otherwise, they remain pure. If it is impossible to distinguish between the pure and the impure, then all of them are ruled to be impure, because the impurity of one of the garments is certain, and there is doubt about which one it is. Prayer is not valid except with a garment whose purity is confirmed.