The arrays of strings are a 2-dimensional array that stores characters in it. In C++ language we have an inbuilt function, with syntax − Syntax swap (first_datatype, second_datatype) which is used to perform swap operations on two elements, that is, exchange the values they carry. In the following, we are also supposed to do some exchange in positions of the elements of the string to get the expected output. However, we can get our output in a much easier way. Problem Statement Now, in this problem, we are provided with two arrays of strings (meaning arrays or ... Read More

A queue is a data structure which follows a FIFO (First In First Out) delivery method that is, the order of a set of messages is strictly preserved. It processes all messages exactly once, hence, there's no duplication of messages. The advantage of a FIFO system over a standard delivery method is because of a queue's ability to support unlimited throughput due to the application of batch-processing of queues. FIFO has high throughput (amount of items passing through a process) and can process a lot more messages than average. In Python, queues can be implemented via two main ... Read More

In this problem, we need to remove the characters from the string whose frequency is not the power of 2. After that, we need to sort each string of the array in non-increasing order. Problem statement- We have given an array arr[] containing total N strings of different lengths. We need to remove the character from the string if its frequency is not the power of 2. After that, we need to sort each string Sample examples Input – arr[] = {"abde", "cpcc", "ddddd", "kk"} Output – edba, p, kk Explanation In the string ‘abde’ string, all characters' frequency is ... Read More

In this problem, we need to reorder the characters of a given string to valid English representations of digits. The first approach can be to find all permutations of the string, extract the English words related to numeric digits, and convert them to digits. Another approach that can be used to solve the problem is by finding one unique character from each word. In this tutorial, we will learn both approaches to solving the given problem. Problem statement- We have given a sting containing lowercase characters and a length equal to N. The string contains the English word representation of ... Read More

In this problem, we have given the email string containing the ‘dot’ and ‘at’ words. We need to replace them with ‘.’ And ‘@’ characters. Note – The valid email address should contain the ‘@’ character only once. It should contain any prefixes before the ‘@’ character and the domain name after that. Also, a valid email can contain multiple ‘.’ Characters. Furthermore, the ‘@’ and ‘.’ Characters should not be at the start or end of the email address. Problem statement – We have given a string str containing the email address, and the length of the string is equal ... Read More

In this problem, we need to count the total number of strings of the given string containing an equal number of lowercase and uppercase characters. The naïve approach to solving the problem is to find all substrings and count the total number of substrings with an equal number of lowercase and uppercase characters. The efficient approach is using the subarray sum problem. We can consider lowercase characters as -1 and uppercase characters as +1, and we will learn both approaches to solve the problem. Problem statement- We have given string str containing the lowercase and uppercase alphabetical characters. We need ... Read More

In this problem, we need to right-shift each character of a given string by its frequency. To solve the problem, we can count the frequency of each character and store it in a data structure like an array or map. After that, we can use the ASCII values of the characters to right-shift each character by their frequency. Problem statement- We have given string str containing lowercase characters and a length equal to N. We need to right-shift each character of the string by the frequency of that particular character in the given string. Sample examples Input – str = ‘tutorialspoint’ ... Read More

In this problem, we need to construct the str2 by using the subsequences of the str1. To solve the problem, we can find subsequences of the str1 so that it can cover the substring with a maximum length of str2. Here, we will learn two different approaches to solving the problem. Problem statement – We have given two strings, str1, and str2, of different lengths. We need to construct the str2 from the str1 by following the condition below. Pick any subsequence from the str1, and append it to the new string, which is empty initially. We need to return ... Read More

In this problem, we have given a string containing 0, 1, and ? characters. We need to find permutations of the string by replacing ‘?’ with 0 and 1. The logic to solve the problem is that we can replace every ‘?’ with either 0 or 1. So, by replacing one ‘?’, we can generate two different permutations, and by replacing N ‘?’ with 2 possibilities, we can generate 2^N permutations. In this tutorial, we will learn two different approaches to solving the given problem. Problem statement – We have given string str containing ‘0’, ‘1’ and ‘?’ characters. We ... Read More

In this problem, we need to select the pair of strings and swap their first character. After that, we need to count the total number of new pairs. We can solve the problem by swapping the first character of each pair and checking whether it exists in the array. The efficient approach to solve the problem can be using the hashmap data structure. Problem statement – We have given an array containing N strings. We can take any of two strings from all array elements and swap the first characters of both strings. We need to count the total ... Read More