Python - Maximum of Similar Keys in Tuples

Python - Maximum of Similar Keys in Tuples

In this tutorial, we'll explore how to find the maximum value among similar keys in a list of tuples in Python.

Problem Statement:

Given a list of tuples, where each tuple contains a key and a value, for every unique key, determine its maximum value.

Example:

Input:

tuples_lst = [('a', 3), ('b', 5), ('a', 7), ('b', 2), ('c', 6)]

Output:

{'a': 7, 'b': 5, 'c': 6}

Step-by-Step Solution:

  1. Initialize a Dictionary: We'll use a dictionary to store the maximum value for each key.
  2. Traverse the Tuple List: For each tuple in the list, if the key exists in the dictionary and its value is smaller than the current tuple's value, update it. If the key doesn't exist, add it.
  3. Return the Result: Return the dictionary containing the maximum values for each key.

Here's the implementation:

def max_of_similar_keys(tuples_lst): # Step 1: Initialize a Dictionary max_values = {} # Step 2: Traverse the Tuple List for key, value in tuples_lst: if key in max_values: if value > max_values[key]: max_values[key] = value else: max_values[key] = value # Step 3: Return the Result return max_values # Test tuples_lst = [('a', 3), ('b', 5), ('a', 7), ('b', 2), ('c', 6)] print("Maximum of similar keys:", max_of_similar_keys(tuples_lst)) # Expected Output: Maximum of similar keys: {'a': 7, 'b': 5, 'c': 6}

Explanation:

For the list tuples_lst given above:

  • For the key 'a', the values are 3 and 7. The maximum value is 7.
  • For the key 'b', the values are 5 and 2. The maximum value is 5.
  • For the key 'c', the value is 6.

The solution uses a dictionary to store and update the maximum values for each key. The time complexity of this solution is O(n), where n is the number of tuples in the list.

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unique-constraint nine-patch preferences junit5 autocompletetextview sybase cross-platform textview infinity xcode7

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