Frequency Encoding

Problem

Frequency-encode categories by their occurrence count.

Return a dict mapping str(category) to its count. Empty input returns {}.

Hint

Count each distinct category and stringify the keys.

case 1

in: [["a","b","a","c","a"]]

expected: {"a":3,"b":1,"c":1}

case 2

in: [[1,1,1]]

expected: {"1":3}

case 3

in: [["x","y","x"]]

expected: {"x":2,"y":1}

case 4

in: [[]]

expected: {}

Starter codePython

def frequency_encode(categories):
    # Your code here
    pass

4 test cases · run your code against them in the editor