tell me the difference between the total amount of the input and the output for patient 29410 since 10/18/2100.
select ( select sum(inputevents_cv.amount) from inputevents_cv where inputevents_cv.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 29410 ) ) and strftime('%y-%m-%d',inputevents_cv.charttime) >= '2100-10-18' ) - ( select sum(outputevents.value) from outputevents where outputevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 29410 ) ) and strftime('%y-%m-%d',outputevents.charttime) >= '2100-10-18' )