Skip to content
Related Articles

Related Articles

Python program to Mark duplicate elements in string
  • Last Updated : 24 Jan, 2021

Given a list, the task is to write a Python program to mark the duplicate occurrence of elements with progressive occurrence number.

Input : test_list = [‘gfg’, ‘is’, ‘best’, ‘gfg’, ‘best’, ‘for’, ‘all’, ‘gfg’]

Output : [‘gfg1’, ‘is’, ‘best1’, ‘gfg2’, ‘best2’, ‘for’, ‘all’, ‘gfg3’]

Explanation : gfg’s all occurrence are marked as it have multiple repetitions(3).

Input : test_list = [‘gfg’, ‘is’, ‘best’, ‘best’, ‘for’, ‘all’]



Output : [‘gfg’, ‘is’, ‘best1’, ‘best2’, ‘for’, ‘all’]

Explanation : best’s all occurrence are marked as it have multiple repetitions(2).

Method 1: Using count() + enumerate() + list comprehension + slicing 

In this, in order to get the duplicate count, the list is sliced to current element index, and count of occurrence of that element till current index is computed using count() and append.

Python3

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate working of
# Mark duplicate elements
# Using count() + enumerate() + list comprehension + slicing 
  
# initializing list
test_list = ["gfg", "is", "best", "gfg"
             "best", "for", "all", "gfg"]
               
# printing original list
print("The original list is : " + str(test_list))
  
# getting count till current using count() and slicing
res = [val + str(test_list[:idx].count(val) + 1) if test_list.count(val) > 1 else val for idx,
       val in enumerate(test_list)]
  
# printing result
print("Duplicates marked List : " + str(res))

chevron_right


Output:

The original list is : [‘gfg’, ‘is’, ‘best’, ‘gfg’, ‘best’, ‘for’, ‘all’, ‘gfg’]

Duplicates marked List : [‘gfg1’, ‘is’, ‘best1’, ‘gfg2’, ‘best2’, ‘for’, ‘all’, ‘gfg3’]

Method 2: Using map() + count() + lambda

Similar to the above method, the only difference being map() is used to get a function using lambda to extend to whole list elements.

Python3

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 code to demonstrate working of
# Mark duplicate elements
# Using map() + count() + lambda
  
# initializing list
test_list = ["gfg", "is", "best", "gfg"
             "best", "for", "all", "gfg"]
               
# printing original list
print("The original list is : " + str(test_list))
  
# getting count till current using count() and slicing
res = list(map(lambda ele: ele[1] + str(test_list[ : ele[0]].count(ele[1]) + 1) if test_list.count(ele[1]) > 1 else ele[1],
               enumerate(test_list)))
  
# printing result
print("Duplicates marked List : " + str(res))

chevron_right


Output:

The original list is : [‘gfg’, ‘is’, ‘best’, ‘gfg’, ‘best’, ‘for’, ‘all’, ‘gfg’]

Duplicates marked List : [‘gfg1’, ‘is’, ‘best1’, ‘gfg2’, ‘best2’, ‘for’, ‘all’, ‘gfg3’]

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course.

My Personal Notes arrow_drop_up
Recommended Articles
Page :