ALGORITHM/METHOD


Step1: prompt the user for earlier time and read earlier time

Step2: prompt the user for later time and read later time

Step3: 

earlierTime = "9:36aM" for example

we need to extract 

hour1 = 9
minute1 = 36
ampm1 = "AM"

from earlier time

Step 4:

same as in step 3 for laterTime = "6:22PM"

hour2 = 6
minute2 = 22
ampm2 = "PM"

Step 5: Find difference in the times

- convert hour1,minute1,ampm1 into minutes1
  example 9.36 AM
  (0+9)x60 + 36

- convert hour2,minute2,ampm2 into minutes2
  example  6.22 PM
  (12+6)x60 + 22


if time is AM then minutes1 = hour1*60+minute1
else minutes1 = (12+hour1)*60+minute1


answer is minutes2 - minutes1

then convert answer to hours/minutes