World cup problem

In the next world cup of cricket there will be 12 teams, equally divided in 2 groups. Team of each group will play a match against each other. From each group, 3 top team will qualify for the next round.(now group is not there). In this round each team will play against each other. Four top teams of this round will qualify for the semi-final round, where the teams will play against the other once. Two winning teams will go to the final round , they will play the best of 3 matches. Find the minimum number of matches to be played in the next world cup.