A singles tournament had six players. Each player played every other player only once, with no ties. If Helen won $$4$$ games, Ines won $$3$$ games, Janet won $$2$$ games, Kendra won $$2$$ games and Lara won $2$ games, how many games did Monica (the sixth player) win? ($$2006 \text{ AMC } 8$$ Problem, Question \#$$20$$) 
Overseas Competition->Knowledge Point->Counting Modules->Permutations and Combinations->Combinations
There are $$6$$ players, so there are $$6\times5\div2=15$$ games in total. By now, $$4+3+2+2+2=13$$ games have been finished (there is one winner in each game), so Monica needs to win $$15-13=2$$ games. Therefore, the answer is $$\rm C$$. 