Input
200 400 150 20 2 6
Output
2 friends. Cost per person by plane: 200. Cost per person by car: 295 3 friends. Cost per person by plane: 200. Cost per person by car: 203 4 friends. Cost per person by plane: 200. Cost per person by car: 195 5 friends. Cost per person by plane: 200. Cost per person by car: 160 6 friends. Cost per person by plane: 200. Cost per person by car: 203 The optimal number of friends are: 5, and the total cost going by car is 800