﻿ Python: Create a dictionary with the unique values of a list as keys and their frequencies as the values - w3resource

# Python: Create a dictionary with the unique values of a list as keys and their frequencies as the values

## Python List: Exercise - 241 with Solution

Write a Python program to create a dictionary with the unique values of a given list as keys and their frequencies as the values.

• Use collections.defaultdict() to store the frequencies of each unique element.
• Use dict() to return a dictionary with the unique elements of the list as keys and their frequencies as the values.

Sample Solution:

Python Code:

``````from collections import defaultdict
def frequencies(lst):
freq = defaultdict(int)
for val in lst:
freq[val] += 1
return dict(freq)
print(frequencies(['a', 'b', 'f', 'a', 'c', 'e', 'a', 'a', 'b', 'e', 'f']))
print(frequencies([3,4,7,5,9,3,4,5,0,3,2,3]))
```
```

Sample Output:

```{'a': 4, 'b': 2, 'f': 2, 'c': 1, 'e': 2}
{3: 4, 4: 2, 7: 1, 5: 2, 9: 1, 0: 1, 2: 1}
```

Flowchart:

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## Python: Tips of the Day

```print(2_000_000)
```2000000