Python: Get the k most frequent elements from a given non-empty list of words using Heap queue algorithm
Python heap queue algorithm: Exercise-14 with Solution
Write a Python program to get the k most frequent elements from a given non-empty list of words using Heap queue algorithm.
Note:
Range of k, 1 ≤ k ≤ number of unique elements and input words contain only lowercase letters.
Sample Solution:
Python Code:
import heapq
from collections import Counter
class Solution:
def top_K_Frequent(self, words, k):
"""
:type words: List[str]
:type k: int
:return type: List[str]
"""
ctr = Counter(words)
heap = [(-ctr[word], word) for word in ctr]
heapq.heapify(heap)
return [heapq.heappop(heap)[1] for _ in range(k)]
if __name__ == '__main__':
words = ["a", "abc", "abcdef", "a", "abcd", "abcd", "abc", "abcdefg"]
k = 3
s = Solution()
print("3 most frequent elements:")
print(s.top_K_Frequent(words, k))
Sample Output:
3 most frequent elements: ['a', 'abc', 'abcd']
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Next: Write a Python program to check if the letters of a given string can be rearranged so that two characters that are adjacent to each other are different using Heap queue algorithm.
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Find current directory and file's directory:
To get the full path to the directory a Python file is contained in, write this in that file:
import os dir_path = os.path.dirname(os.path.realpath(__file__))
(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)
To get the current working directory use
import os cwd = os.getcwd()
Documentation references for the modules, constants and functions used above:
- The os and os.path modules.
- The __file__ constant
- os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
- os.path.dirname(path) (returns "the directory name of pathname path")
- os.getcwd() (returns "a string representing the current working directory")
- os.chdir(path) ("change the current working directory to path")
Ref: https://bit.ly/3fy0R6m
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