instruction: calculate patient 15119's length of stay in the icu for the last time.
response: SELECT STRFTIME('%j', icustays.outtime) - STRFTIME('%j', icustays.intime) FROM icustays WHERE icustays.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 15119) AND NOT icustays.outtime IS NULL ORDER BY icustays.intime DESC LIMIT 1