i am looking for information in cambridge
user
what do you want to know ?
assistant
i should have told you that already , i apologize . i need to take a train from cambridge to london kings cross , on thursday leaving after 15:00 .
user
there are trains meeting those requirement -s leaving at 15:00 , 17:00 , 19:00 , 21:00 , 23:00 . they all take 51 minutes and cost 23.60 pounds .
assistant
i think i want the 1 leaving at 17:00 . what s the train id for that 1 ?