String Data Structure
Learn more about String in DSA Self Paced Course
Practice Problems on String
What is String?
Strings are defined as an array of characters. The difference between a character array and a string is the string is terminated with a special character ‘\0’.
Below are some examples of strings:
“geeks”, “for”, “geeks”, “GeeksforGeeks”, “Geeks for Geeks”, “123Geeks”, “@123 Geeks”
How String is represented in Memory?
In C, a string can be referred to either using a character pointer or as a character array. When strings are declared as character arrays, they are stored like other types of arrays in C. For example, if str[] is an auto variable then the string is stored in the stack segment, if it’s a global or static variable then stored in the data segment, etc.
What is String & How String is represented in Memory
Topics:
- Searching For Characters and Substring in a String
- Program to reverse a string (Iterative and Recursive)
- Left Rotation and Right Rotation of a String
- Sort string of characters
- Print the frequency of each character in Alphabetical order
- Swap characters in a String
- C program to find the length of a string
- How to insert characters in a string at a certain position?
- Program to check if two strings are same or not
- Concatenating Two Strings
- Remove all occurrences of a character in a string
- Change if all bits can be made same by single flip
- Number of flips to make binary string alternate
- Binary representation of next number
- Min flips of continuous characters to make all characters same in a string
- Generate all binary strings without consecutive 1’s
- Find i’th Index character in a binary string obtained after n iterations
- Generate n-bit Gray Codes
- Program to print all substrings of a given string
- Print all subsequences of a string
- Count Distinct Subsequences
- Count distinct occurrences as a subsequence
- Longest Common Subsequence
- Shortest Superstring Problem
- Printing Shortest Common Supersequence
- Shortest Common Supersequence
- Longest Repeating Subsequence
- Longest Palindromic Subsequence
- Longest Palindromic Substring using Dynamic Programming
- C Program to Check if a Given String is Palindrome
- Check if a given string is a rotation of a palindrome
- Check if characters of a given string can be rearranged to form a palindrome
- Online algorithm for checking palindrome in a stream
- Print all palindromic partitions of a string
- Minimum characters to be added at front to make string palindrome
- Make largest palindrome by changing at most K-digits
- Minimum number of deletions to make a string palindrome
- Minimum insertions to form a palindrome with permutations allowed
- Naive algorithm for Pattern Searching
- KMP Algorithm for Pattern Searching
- Z algorithm
- Search a Word in a 2D Grid of characters
- Wildcard Pattern Matching
- Aho-Corasick Algorithm
- Find all strings that match specific pattern in a dictionary
- Check if string follows order of characters defined by a pattern or not
- Easy:
- Count strings with consecutive 1’s
- Generate all binary strings from given pattern
- Add n binary strings
- Divide large number represented as string
- Program to find Smallest and Largest Word in a String
- Count number of equal pairs in a string
- Camel case of a given sentence
- Second most repeated word in a sequence
- Print all possible strings that can be made by placing spaces
- Check if all levels of two trees are anagrams or not
- Medium:
- K’th Non-repeating Character
- Queries for characters in a repeated string
- URLify a given string (Replace spaces is %20)
- Count of total anagram substrings
- Count number of binary strings without consecutive 1’s
- Lexicographically next string
- Check if given string can be split into four distinct strings
- Word Break Problem
- Check for balanced parentheses in an expression | O(1) space
- Length of Longest Balanced Subsequence
- Minimum Swaps for Bracket Balancing
- Convert a sentence into its equivalent mobile numeric keypad sequence
- Burrows – Wheeler Data Transform Algorithm
- Form minimum number from given sequence
- Print shortest path to print a string on screen
- Mirror characters of a string
- Hard:
- Multiply Large Numbers represented as Strings
- Count ways to increase LCS length of two strings by one
- Minimum rotations required to get the same string
- Find if an array of strings can be chained to form a circle
- Given a sorted dictionary of an alien language, find order of characters
- Remove minimum number of characters so that two strings become anagram
- Minimum Number of Manipulations required to make two Strings Anagram Without Deletion of Character
- Palindrome Substring Queries
- Powet Set in Lexicographic order
- Minimum Word Break
- Minimum number of bracket reversals needed to make an expression balanced
- Word Wrap problem ( Space optimized solution )
- Decode a string recursively encoded as count followed by substring
Recomended:
If you like GeeksforGeeks and would like to contribute, you can also write an article and mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
