問題
With inheritance, a subclass reuses its parent's behaviour and adds its own. Every vehicle pays a toll; a truck is a vehicle that pays extra for its axles.
Each vehicle is one of:
motorbike: pays 2.car: pays 5.truck <axles>: pays the car rate 5, plus 3 for every axle beyond the first two.
Implement vehicle_tolls(vehicles).
Input
vehicles: The vehicles passing the toll gate.
Output
Return the total toll collected.
制約
0 ≤ number of vehicles ≤ 100,000
2 ≤ axles ≤ 10
例
例 1
入力：
vehicles = ["car", "motorbike", "truck 4"]
期待される出力：
expected = 18入力：
std::vector<std::string> vehicles = {"car", "motorbike", "truck 4"};
期待される出力：
long long expected = 18;入力：
string[] vehicles = new string[] {"car", "motorbike", "truck 4"};
期待される出力：
long expected = 18;解説
5 + 2 + (5 + 3 × 2) = 18.
例 2
入力：
vehicles = ["truck 2", "truck 3"]
期待される出力：
expected = 13入力：
std::vector<std::string> vehicles = {"truck 2", "truck 3"};
期待される出力：
long long expected = 13;入力：
string[] vehicles = new string[] {"truck 2", "truck 3"};
期待される出力：
long expected = 13;解説
A 2-axle truck pays just the car rate 5; a 3-axle truck pays 5 + 3 = 8. Total 13.
解き方のヒント
まずは自分で考えてから、ヒントを 1 つずつ開いてみましょう。
ヒント 1
Start from the car rate of 5 and adjust per vehicle type.
ヒント 2
A truck pays extra only for axles beyond the first two.
ヒント 3
Motorbikes override the base rule with a fixed 2.
目安の計算量
O(number of vehicles) time, O(1) extra space
参考資料
この課題はCodeUtility用に調整されています。上記の説明と制約に従ってください。