Python: Map the values of a list to a dictionary using a function

Last update on April 19 2025 13:01:10 (UTC/GMT +8 hours)

Map List to Dictionary

Write a Python program to map the values of a list to a dictionary using a function, where the key-value pairs consist of the original value as the key and the result of the function as the value.

Use map() to apply fn to each value of the list.
Use zip() to pair original values to the values produced by fn.
Use dict() to return an appropriate dictionary.

Sample Solution:

Python Code:

# Define a function called 'map_dictionary' that takes an iterable 'itr' and a function 'fn' as arguments.
def map_dictionary(itr, fn):
  # Create a dictionary by zipping the iterable 'itr' and the result of applying the function 'fn' to each element in 'itr'.
  return dict(zip(itr, map(fn, itr)))

# Example usage: Use the 'map_dictionary' function to create a dictionary where the keys are elements from the list [1, 2, 3] and the values are the squares of those elements.
print(map_dictionary([1, 2, 3], lambda x: x * x))

Sample Output:

{1: 1, 2: 4, 3: 9}

Flowchart:

For more Practice: Solve these Related Problems:

Write a Python program to map a list of strings to a dictionary where each string is paired with its length.
Write a Python program to map a list of numbers to a dictionary where each key is a number and the value is its square.
Write a Python program to map a list of tuples to a dictionary using the first element as the key and the second as the value.
Write a Python program to map elements of a list to a dictionary where keys are the original values and values are the result of applying a lambda function to each element.

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