Python Collections.OrderedDict() Solution
collections.OrderedDict
An OrderedDict is a dictionary that remembers the order of the keys that were inserted first. If a new entry overwrites an existing entry, the original insertion position is left unchanged.
Example
>>> from collections import OrderedDict
>>>
>>> ordinary_dictionary = {}
>>> ordinary_dictionary['a'] = 1
>>> ordinary_dictionary['b'] = 2
>>> ordinary_dictionary['c'] = 3
>>> ordinary_dictionary['d'] = 4
>>> ordinary_dictionary['e'] = 5
>>>
>>> print ordinary_dictionary
{'a': 1, 'c': 3, 'b': 2, 'e': 5, 'd': 4}
>>>
>>> ordered_dictionary = OrderedDict()
>>> ordered_dictionary['a'] = 1
>>> ordered_dictionary['b'] = 2
>>> ordered_dictionary['c'] = 3
>>> ordered_dictionary['d'] = 4
>>> ordered_dictionary['e'] = 5
>>>
>>> print ordered_dictionary
OrderedDict([('a', 1), ('b', 2), ('c', 3), ('d', 4), ('e', 5)])
Task
You are the manager of a supermarket.
You have a list of N items together with their prices that consumers bought on a particular day.
Your task is to print each item_name and net_price in order of its first occurrence.
item_name = Name of the item.
net_price = Quantity of the item sold multiplied by the price of each item.
Input Format
The first line contains the number of items, N.
The next N lines contains the item’s name and price, separated by a space.
Constraints
0 < N <= 100
Output Format
Print the item_name and net_price in order of its first occurrence.
Sample Input
9
BANANA FRIES 12
POTATO CHIPS 30
APPLE JUICE 10
CANDY 5
APPLE JUICE 10
CANDY 5
CANDY 5
CANDY 5
POTATO CHIPS 30
Sample Output
BANANA FRIES 12
POTATO CHIPS 60
APPLE JUICE 20
CANDY 20
Explanation
BANANA FRIES: Quantity bought: 1, Price: 12
Net Price: 12
POTATO CHIPS: Quantity bought: 2, Price: 30
Net Price: 60
APPLE JUICE: Quantity bought: 2, Price: 10
Net Price: 20
CANDY: Quantity bought: 4, Price: 5
Net Price: 20
Solution:
from collections import OrderedDict
a = OrderedDict()
input_ = int(input())
for _ in range(input_):
item, space, price = input().rpartition(' ')
a[item] = a.get(item, 0) + int(price)
for item, price in a.items():
print(item, price)
Steps Used in solving the problem -
Step 1: First, we have imported OrderedDict.
Step 2: Then, we created two variables. The first one is to store our OrderedDict and the second is to take input.
Step 3: In fourth step we have created a for loop in range of our input.
Step 4: Then, we used the input method to take input of item, space, and price. We have used rpartition method to split our inputs in three parts.
Step 5: Then, we created another for loop in a.items.
Step 6: In last step we have printed item and price.
