Have a challenge here and was hoping MS Excel could help in some form or fashion.

I am trying to schedule meetings for businesses within a one or two day time period.
Lets say i have 20 businesses in Group A and 100 businesses in group B. Meetings will not occur between businesses in the same group. Some of the businesses in group A will not meet with some of business in Group B. They are selective meetings. So far i made a simple spreadsheet with Group A listed in Columns and Group B in rows. I then went through and placed a 1 in the interesting cell if the two businesses need to meet. So i have all the meetings i want to take place and who they are to take place between mapped out. Now comes the hard part of scheduling the times. Obviously a business cant be in two meetings at once. What do you suggest i do? SHould i just do it by hand....this can be very time consuming especially if there are cancelation. Or is there a function in excel that will help me. each meeting is 45 minutes long, and i am planing to have them on one day with a runover happening on day 2 (or 3 as needed)

Suggetsions!