toaco · February 15, 2019 01:36 · Feb 15, 2019 · Feb 15, 2019
diff --git a/solution.py b/solution.py
@@ -1,4 +1,4 @@
-# encoding: utf-8
+# -*- coding: utf-8 -*-
 import datetime
 from collections import defaultdict
 
@@ -65,8 +65,9 @@ def find_way(self, departing_flights, returning_flights):
                         min_amount = amount
                         amount_map[min_amount].append((df, rf))
 
-        flights = amount_map[min_amount]
-        return flights[-1]  # FLIGHTS有序，返回最后一个
+        flights = amount_map.get(min_amount)
+        if flights:
+            return flights[-1]  # FLIGHTS有序，返回最后一个
 
     def is_available_way(self, departing_flight, returning_flight):
         start_time = self.earliest_time(departing_flight)
@@ -135,6 +136,10 @@ def prev_weekend(cls, date):
     flight_finder = FlightFinder('reward',
                                  datetime.date(2016, 04, 10),
                                  datetime.date(2016, 04, 20))
-    departing_flight, returning_flight = flight_finder.run()
-    print departing_flight['name']
-    print returning_flight['name']
+    flights = flight_finder.run()
+    if flights:
+        departing_flight, returning_flight = flights
+        print departing_flight['name']
+        print returning_flight['name']
+    else:
+        print 'cannot find flights'
diff --git a/solution.py b/solution.py
@@ -0,0 +1,140 @@
+# encoding: utf-8
+import datetime
+from collections import defaultdict
+
+FLIGHTS = {
+    "chengdu_to_xian": {
+        "reward": [
+            {'name': 'GD2501', 'time': '08:00', 'price': 500, 'at_weekends': True},
+            {'name': 'GD2501', 'time': '08:00', 'price': 800, 'at_weekends': False},
+            {'name': 'GD2606', 'time': '12:25', 'price': 500, 'at_weekends': True},
+            {'name': 'GD2606', 'time': '12:25', 'price': 1100, 'at_weekends': False},
+            {'name': 'GD8732', 'time': '19:30', 'price': 400, 'at_weekends': True},
+            {'name': 'GD8732', 'time': '19:30', 'price': 1000, 'at_weekends': False},
+        ],
+        "regular": [
+            {'name': 'GD2501', 'time': '08:00', 'price': 900, 'at_weekends': True},
+            {'name': 'GD2501', 'time': '08:00', 'price': 1100, 'at_weekends': False},
+            {'name': 'GD2606', 'time': '12:25', 'price': 600, 'at_weekends': True},
+            {'name': 'GD2606', 'time': '12:25', 'price': 1600, 'at_weekends': False},
+            {'name': 'GD8732', 'time': '19:30', 'price': 1500, 'at_weekends': True},
+            {'name': 'GD8732', 'time': '19:30', 'price': 2200, 'at_weekends': False},
+        ],
+    },
+    "xian_to_chengdu": {
+        "reward": [
+            {'name': 'GD2502', 'time': '12:00', 'price': 800, 'at_weekends': True},
+            {'name': 'GD2502', 'time': '12:00', 'price': 800, 'at_weekends': False},
+            {'name': 'GD2607', 'time': '16:25', 'price': 500, 'at_weekends': True},
+            {'name': 'GD2607', 'time': '16:25', 'price': 1100, 'at_weekends': False},
+            {'name': 'GD8733', 'time': '23:30', 'price': 400, 'at_weekends': True},
+            {'name': 'GD8733', 'time': '23:30', 'price': 1500, 'at_weekends': False},
+        ],
+        "regular": [
+            {'name': 'GD2502', 'time': '12:00', 'price': 900, 'at_weekends': True},
+            {'name': 'GD2502', 'time': '12:00', 'price': 1700, 'at_weekends': False},
+            {'name': 'GD2607', 'time': '16:25', 'price': 600, 'at_weekends': True},
+            {'name': 'GD2607', 'time': '16:25', 'price': 1600, 'at_weekends': False},
+            {'name': 'GD8733', 'time': '23:30', 'price': 1000, 'at_weekends': True},
+            {'name': 'GD8733', 'time': '23:30', 'price': 1600, 'at_weekends': False},
+        ],
+    }
+}
+
+
+class FlightFinder(object):
+    def __init__(self, customer_type, departing_date, returning_date):
+        self.customer_type = customer_type
+        self.departing_date = departing_date
+        self.returning_date = returning_date
+
+    def run(self):
+        departing_flights = FLIGHTS['chengdu_to_xian'][self.customer_type]
+        returning_flights = FLIGHTS['xian_to_chengdu'][self.customer_type]
+        return self.find_way(departing_flights, returning_flights)
+
+    def find_way(self, departing_flights, returning_flights):
+        min_amount = float('+inf')
+        amount_map = defaultdict(list)
+
+        for df in departing_flights:
+            for rf in returning_flights:
+                if self.is_available_way(df, rf):
+                    amount = self.get_amount(df, rf)
+                    if amount <= min_amount:
+                        min_amount = amount
+                        amount_map[min_amount].append((df, rf))
+
+        flights = amount_map[min_amount]
+        return flights[-1]  # FLIGHTS有序，返回最后一个
+
+    def is_available_way(self, departing_flight, returning_flight):
+        start_time = self.earliest_time(departing_flight)
+        return_time = self.latest_time(returning_flight)
+        if start_time and return_time and start_time < return_time:
+            return True
+
+    def earliest_time(self, flight):
+        if flight['at_weekends']:
+            date = DateHelper.next_weekend(self.departing_date)
+        else:
+            date = DateHelper.next_weekday(self.departing_date)
+        if date <= self.returning_date:
+            hour, minute = map(lambda x: int(x), flight['time'].split(':'))
+            return datetime.datetime.combine(date, datetime.time(hour, minute))
+
+    def latest_time(self, flight):
+        if flight['at_weekends']:
+            date = DateHelper.prev_weekend(self.returning_date)
+        else:
+            date = DateHelper.prev_weekday(self.returning_date)
+        if date >= self.departing_date:
+            hour, minute = map(lambda x: int(x), flight['time'].split(':'))
+            return datetime.datetime.combine(date, datetime.time(hour, minute))
+
+    @staticmethod
+    def get_amount(departing_flight, returning_flight):
+        return departing_flight['price'] + returning_flight['price']
+
+
+class DateHelper(object):
+    @classmethod
+    def next_weekday(cls, date):
+        weekday = date.weekday()
+        if weekday < 5:
+            return date
+        else:
+            return date + datetime.timedelta(days=7 - weekday)
+
+    @classmethod
+    def next_weekend(cls, date):
+        weekday = date.weekday()
+        if weekday > 4:
+            return date
+        else:
+            return date + datetime.timedelta(days=5 - weekday)
+
+    @classmethod
+    def prev_weekday(cls, date):
+        weekday = date.weekday()
+        if weekday < 5:
+            return date
+        else:
+            return date + datetime.timedelta(days=4 - weekday)
+
+    @classmethod
+    def prev_weekend(cls, date):
+        weekday = date.weekday()
+        if weekday > 4:
+            return date
+        else:
+            return date + datetime.timedelta(days=-1 - weekday)
+
+
+if __name__ == '__main__':
+    flight_finder = FlightFinder('reward',
+                                 datetime.date(2016, 04, 10),
+                                 datetime.date(2016, 04, 20))
+    departing_flight, returning_flight = flight_finder.run()
+    print departing_flight['name']
+    print returning_flight['name']