Python – Case Insensitive string counter

Given a List of Strings, find frequency of strings case insensitive.

Input : test_list = [“Gfg”, “Best”, “GFG”, “is”, “IS”, “BEST”]
Output : {‘gfg’: 2, ‘best’: 2, ‘is’: 2}
Explanation : All occur twice.

Input : test_list = [“Gfg”, “gfg”, “GFG”]
Output : {‘gfg’: 3}
Explanation : Only “gfg” 3 occurrences.

Method : Using defaultdict() + lower()

In this, we perform lower() to all the strings, before mapping in defaultdict. This ensures case insensitivity while mapping and cumulating frequency.






# Python3 code to demonstrate working of 
# Strings Frequency (Case Insensitive)
# Using defaultdict() + lower()
from collections import defaultdict
# initializing list
test_list = ["Gfg", "Best", "best", "gfg", "GFG", "is", "IS", "BEST"]
# printing original list
print("The original list is : " + str(test_list))
res = defaultdict(int)
for ele in test_list:
    # lowercasing to cater for Case Insensitivity
    res[ele.lower()] += 1
# printing result 
print("Strings Frequency : " + str(dict(res)))



The original list is : ['Gfg', 'Best', 'best', 'gfg', 'GFG', 'is', 'IS', 'BEST']
Strings Frequency : {'gfg': 3, 'best': 3, 'is': 2}

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