Remove consecutive duplicate characters in a string python. Feb 6, 2026 · However, a frequent pitfall is ending up with empty strings in the result—especially when delimiters are consecutive, leading, or trailing. Mar 10, 2024 · Regular expressions are a powerful tool for string manipulation and can be applied to remove consecutive duplicates. )\\1+ to match adjacent duplicated characters. Mar 3, 2024 · Problem Formulation: When working with strings in Python, you might encounter situations where a string contains duplicate characters that you want to remove. But what I want to keep is '1232152', only removing the consecutive duplicates. So, if the input is like s = "xyyyxxz", then the output will be "z", as "yyy" are the first consecutive duplicate characters which will be deleted. It can also be used to remove line breaks, replace text, change text case, strip html tags, remove whitespaces, and many more. In Python, the `re` module (regular expressions) is a powerful tool for handling complex string splitting. fromkeys () This method converts the string into a dictionary where each character is a key. How can I remove duplicate words in a string with Python? Asked 14 years, 4 months ago Modified 2 years, 6 months ago Viewed 100k times. Mar 23, 2012 · 74 How can I remove duplicate characters from a string using Python? For example, let's say I have a string: For a string such as '12233322155552', by removing the duplicates, I can get '1235'. We’ll cover core regex concepts, step-by-step implementation, real-world examples, troubleshooting, and best practices. You must make sure your result is the smallest in lexicographical order among all possible results. Using dict. Feb 10, 2026 · Text Cleaner Text Cleaner is a text cleaning and text formatting online tool. The task is to remove all duplicate characters from the string and find the resultant string. Dec 11, 2025 · In this guide, we’ll break down how to use regex to detect and eliminate repeated character patterns. Contribute to vitornns/leetcode-py-solutions development by creating an account on GitHub. It then replaces these sequences of consecutive duplicates with just a single occurrence of that character. Remove Duplicate Letters - Given a string s, remove duplicate letters so that every letter appears once and only once. Feb 2, 2026 · This idea is that regular expression to match any character followed by one or more of the same character in a string. Method 1: Using a For Loop This method involves iterating over the characters in the string and building Mar 22, 2013 · def my_function(string, lett): newString = "" for char in string: #all characters for s in string: #character I'm testing if s == s+1: newString+=lett # if there are multiple occurrences of s, replace with lett since its a single char anyway else: newString+=char #if not a duplicate, add next char to newString return newString #TypeError: cannot concatenate 'str' and 'int' objects What't going Sep 14, 2013 · How can I remove duplicate characters from a string using Python? For example, let's say I have a string: foo = "SSYYNNOOPPSSIISS" How can I make the string: foo = SYNOPSIS I'm new to python and Nov 4, 2025 · The task is to remove all duplicate characters from a string while keeping the first occurrence of each character in its original order. Also once you are done with remove_dups you should break out since you are no longer interested in the same you just modified. In this tutorial, we will look at how to remove consecutive duplicates from a string in Python with the help of some examples. Nov 20, 2016 · You should be returning the values of the string, since these are passed by copies. Jul 23, 2025 · Write a Python program for a given string S which may contain lowercase and uppercase characters. Nov 24, 2024 · Explore efficient ways to eliminate duplicate characters from a string in Python, maintaining or disregarding order as needed. For example: Input: "geeksforgeeks" Output: "geksfor" Let’s explore multiple methods to remove duplicates from a string in Python. Then "xxx" will be deleted to end up with "z". For example, given the input string “aabbccdef”, you would want to remove the duplicates to get the output string “abcdef”. 🎓Leetcode solutions in Python 📚. So we have "xxxz". How to remove consecutive duplicates from a string? Jun 12, 2025 · Python Exercises, Practice and Solution: Write a Python program to remove all consecutive duplicates of a given string. We have to find the final string. The Python re module provides regular expression operations, and one can use the pattern (. Since dictionary keys Oct 20, 2020 · Suppose we have a string s, we repeatedly delete the first consecutive duplicate characters. Mar 9, 2024 · Another approach is to use recursion to remove consecutive duplicate characters by successively calling the function on substrings of the original string until there are no duplicates left. luf orp gln pqp jkd iuy nde ogv wbp rxk ues sgt mlh pdw vwr