16 teams enter a competition. They are divided up into four Pools (A, B, C and D) of four teams each. Every team plays one match against the other teams in its pool.

After the Pool matches are completed:

the winner of Pool A plays the second placed team of Pool B

• the winner of Pool B plays the second placed team of Pool A

the winner of Pool C plays the second placed team of Pool D

• the winner of Pool D plays the second placed team of Pool C

The winners of these four matches then play semi-finals, and the winners of the semi-finals play in the final.

How many matches are played altogether?

63

32

23

31