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

Python List: Exercise - 220 with Solution

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:

def map_dictionary(itr, fn):
  return dict(zip(itr, map(fn, itr)))
print(map_dictionary([1, 2, 3], lambda x: x * x))

Sample Output:

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

Flowchart:

Flowchart: Map the values of a list to a dictionary using a function.

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Python: Tips of the Day

Floor Division:

When we speak of division we normally mean (/) float division operator, this will give a precise result in float format with decimals.

For a rounded integer result there is (//) floor division operator in Python. Floor division will only give integer results that are round numbers.

print(1000 // 300)
print(1000 / 300)

Output:

3
3.3333333333333335