Given a particular date, calculate how many months must pass before that same day of the month occurs on the same day of the week.
Start with 22-Oct-2014, which is a Wednesday. How many months must pass before the 22nd of the month occurs on a Wednesday again? Answer: You have to wait for six months. 22-Apr-2015 is also a Wednesday.
d_in = '22-Oct-2014' wait_in_months = 6