Consider the schedule S: w$1($X$)$; r$2($Y$)$; w$2($Y$)$; w$1($Z$)$; w$3($X$)$; c$1$; r$3($Z$)$; c$3$; r$2($X$)$; c$2$;

Consider this list of types of schedules:

Serial

Strict

Cascadeless

Recoverable

What is the smallest number, so that the schedule belongs to that type?