i need to find a train from cambridge on wednesday .
user
the tr3702 takes you to london kings cross . do you need a ticket ?
assistant
no . i would like to go to norwich at 9:30 .
user
do you want to leave at 9:30 or arrive by then ?
assistant
arrive by 9:30 in norwich .
user
what time could you like to depart at ?
assistant
i have no preference for that . can you make a booking for me on the train with the earliest departure time ?