CODE EXAMPLE FOR PYTHON

collections counter

# importing the collections module
import collections
# intializing the arr
arr = [1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3]
# getting the elements frequencies using Counter class
elements_count = collections.Counter(arr)
# printing the element and the frequency
for key, value in elements_count.items():
   print(f"{key}: {value}")