Consider the following scenario. The National Rugby League is a sporting competition involving 16 teams. Unfortunately, this year matches began before the schedule for the whole season was agreed to. The following requirements are to met. Each weekend there are eight matches (with each match involving two teams) and each team plays exactly once each weekend. In the season each pair of teams should play two matches against each other.

So far there have been 17 weekends of matches. Over the first 15 weekends, every pair of teams played one match against each other. On weekends 16 and 17 the following matches were played.

Weekend 16

Cowboys v Broncos

Storm v Warriors

Knights v Raiders

Eels v Panthers

Tigers v Roosters

Sea Eagles v Dragons

Sharks v Bulldogs

Titans v Rabbitohs

Weekend 17

Broncos v Storm

Roosters v Sea Eagles

Dragons v Sharks

Warriors v Knights

Raiders v Eels

Cowboys v Panthers

Bulldogs v Rabbitohs

Titans v Tigers

It is now coming up to the eighteenth weekend and your task is to design a schedule for the remaining matches of the season.