--- id: 691f7773cddba1caf1bf5ecb title: "Challenge 132: Purge Most Frequent" challengeType: 29 dashedName: challenge-132 --- # --description-- Given an array of values, remove all occurrences of the most frequently occurring element and return the resulting array. - If multiple values are tied for most frequent, remove all of them. - Do not change any of the other elements or their order. # --hints-- `purge_most_frequent([1, 2, 2, 3])` should return `[1, 3]`. ```js ({test: () => { runPython(` from unittest import TestCase TestCase().assertEqual(purge_most_frequent([1, 2, 2, 3]), [1, 3])`) }}) ``` `purge_most_frequent(["a", "b", "d", "b", "c", "d", "c", "d", "c", "d"])` should return `["a", "b", "b", "c", "c", "c"]`. ```js ({test: () => { runPython(` from unittest import TestCase TestCase().assertEqual(purge_most_frequent(["a", "b", "d", "b", "c", "d", "c", "d", "c", "d"]), ["a", "b", "b", "c", "c", "c"])`) }}) ``` `purge_most_frequent(["red", "blue", "green", "red", "blue", "green", "blue"])` should return `["red", "green", "red", "green"]`. ```js ({test: () => { runPython(` from unittest import TestCase TestCase().assertEqual(purge_most_frequent(["red", "blue", "green", "red", "blue", "green", "blue"]), ["red", "green", "red", "green"])`) }}) ``` `purge_most_frequent([5, 5, 5, 5])` should return `[]`. ```js ({test: () => { runPython(` from unittest import TestCase TestCase().assertEqual(purge_most_frequent([5, 5, 5, 5]), [])`) }}) ``` `purgeMostFrequent([10, 12, 7, 3, 7, 7, 12, 12])` should return `[10, 3]`. ```js ({test: () => { runPython(` from unittest import TestCase TestCase().assertEqual(purge_most_frequent([10, 12, 7, 3, 7, 7, 12, 12]), [10, 3])`) }}) ``` # --seed-- ## --seed-contents-- ```py def purge_most_frequent(arr): return arr ``` # --solutions-- ```py def purge_most_frequent(arr): freq = {} for val in arr: freq[val] = freq.get(val, 0) + 1 max_freq = max(freq.values()) to_remove = {val for val, count in freq.items() if count == max_freq} return [val for val in arr if val not in to_remove] ```