freecodecamp--freecodecamp/curriculum/challenges/english/blocks/daily-coding-challenges-python/691b559495c5cb5a37b9b481.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
691b559495c5cb5a37b9b481	Challenge 121: Most Frequent	29	challenge-121

--description--

Given an array of elements, return the element that appears most frequently.

• There will always be a single most frequent element.

--hints--

most_frequent(["a", "b", "a", "c"]) should return "a".

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(most_frequent(["a", "b", "a", "c"]), "a")`)
}})

most_frequent([2, 3, 5, 2, 6, 3, 2, 7, 2, 9]) should return 2.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(most_frequent([2, 3, 5, 2, 6, 3, 2, 7, 2, 9]), 2)`)
}})

most_frequent([True, False, "False", "True", False]) should return False.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertIs(most_frequent([True, False, "False", "True", False]), False)`)
}})

most_frequent([40, 20, 70, 30, 10, 40, 10, 50, 40, 60]) should return 40.

({test: () => { runPython(`
from unittest import TestCase
TestCase().assertEqual(most_frequent([40, 20, 70, 30, 10, 40, 10, 50, 40, 60]), 40)`)
}})

--seed--

--seed-contents--

def most_frequent(arr):

    return arr

--solutions--

def most_frequent(arr):
    freq = {}
    max_count = 0
    most_elem = None

    for el in arr:
        freq[el] = freq.get(el, 0) + 1
        if freq[el] > max_count:
            max_count = freq[el]
            most_elem = el

    return most_elem