Python Exercise: Get the n expensive and cheap price items from a given dataset using Heap queue algorithm

Python heap queue algorithm: Exercise-10 with Solution

Write a Python program to get the n expensive and cheap price items from a given dataset using Heap queue algorithm.

Sample Solution:

Python Code:

import heapq
from pprint import pprint
items = [
    {'name': 'Item-1', 'price': 101.1},
    {'name': 'Item-2', 'price': 555.22},
    {'name': 'Item-3', 'price': 45.09},
    {'name': 'Item-4', 'price': 22.75},
    {'name': 'Item-5', 'price': 16.30},
    {'name': 'Item-6', 'price': 110.65}
]

cheap = heapq.nsmallest(3, items, key=lambda s: s['price'])
expensive = heapq.nlargest(3, items, key=lambda s: s['price'])
print("Original datasets:")
pprint(items)
print("\nFirst 3 expensive items:")
pprint(expensive)
print("\nFirst 3 cheap items:")
pprint(cheap)

Sample Output:

Original datasets:
[{'name': 'Item-1', 'price': 101.1},
 {'name': 'Item-2', 'price': 555.22},
 {'name': 'Item-3', 'price': 45.09},
 {'name': 'Item-4', 'price': 22.75},
 {'name': 'Item-5', 'price': 16.3},
 {'name': 'Item-6', 'price': 110.65}]

First 3 expensive items:
[{'name': 'Item-2', 'price': 555.22},
 {'name': 'Item-6', 'price': 110.65},
 {'name': 'Item-1', 'price': 101.1}]

First 3 cheap items:
[{'name': 'Item-5', 'price': 16.3},
 {'name': 'Item-4', 'price': 22.75},
 {'name': 'Item-3', 'price': 45.09}]

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