There are four soccer teams that are competing in a round-robin format. In the event of a draw, $$1$$ point would be awarded to both teams. $$3$$ points would be given to the team that wins and $$0$$ points would be given to the team that loses. The scores of Team $$A$$, $$B$$, $$C$$ and $$D$$ are $$7$$, $$4$$, $$4$$ and $$1$$ point respectively. How many matches ended in a draw? 
Overseas Competition->Knowledge Point->Calculation Modules->Operations with New Definition->Finding Patterns
We can first assume that all games ended in a $win-lose$ scenario.  Number of games played $=3+2+1=6$  Maximum total score $=6\times3=18$  Everytime a $win-lose$ scenario changes to a $draw-draw$ scenario, the total score decreases by $3-2=1$  Difference in score $=18-16=2$  Number of matches that ended in a draw $=2\div1=2$ 