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Get StartedFind the length of the longest contiguous substring of a given string, such that the length of the substring is 2×n digits and the sum of the leftmost n digits is equal to the sum of the rightmost n digits.
Given a string, in-place remove all occurrences of AB and C from it. For example, for the input string is ‘CBAABCAB’, the string after removal of ‘AB’ and ‘C’ is ‘BA’.
Given a text, find all occurrences of a given pattern in it. The goal is to find all occurrences of pattern P[1…m] of length m in the given text T[1…n] of length n.
Given a list of words, efficiently group all anagrams. The two strings, X and Y, are anagrams if by rearranging X’s letters, we can get Y using all the original letters of X exactly once.
Given a string, find first k non-repeating characters in it by doing only a single traversal of it.
Given a list of words and a pattern, find all words in the list that follows the same order of characters as that of the pattern.
Given n lists of characters and a number whose digits lie between 1 and n, print all possible combinations by replacing its digits with the characters of the corresponding list.
Given a sequence of numbers between 2 and 9, print all possible combinations of words formed from the mobile keypad with some digits associated with each key.
Given a string, find all possible palindromic substrings in it. The problem differs from the problem of finding the possible palindromic subsequence. Unlike subsequences, substrings are required to occupy consecutive positions within the original string.
Given two strings, determine whether they are isomorphic. Two strings, X and Y, are called isomorphic if all occurrences of each character in X can be replaced with another character to get Y and vice-versa.
Find all interleavings of given strings that can be formed from all the characters of the first and second string where the order of characters is preserved.
Given a binary pattern containing ? wildcard character at a few positions, find all possible combinations of binary strings that can be formed by replacing the wildcard character by either 0 or 1.