Suppose a man is typing some name on keyboard. Sometimes some buttons are long-pressed by mistake. So it may type one or more extra character. So we will take two strings, and check whether the second string is long-pressed name or not. So if the name is “Amit”, and second string is “Ammittt” is longpressed name. But “Ammttt” is not, because character i is not present here.To solve this, we will follow these steps −let j := 0for i := 0, i < second.size, increase i by 1 −if j < actual_name.size and actual_name[j] = second[i], thenincrease j by 1return ... Read More

Suppose we have a string with letters and numbers. We have to generate all possible combinations of that string by taking uppercase and lowercase versions of letters that are present in the string. So if one string has only numbers, only that will be returned. Suppose the string is like “1ab2”, then the strings will be [“1ab2”, “1Ab2”, “1aB2”, “1AB2”]To solve this problem, we will use recursive approach. It takes the index parameter to start work from that index. It also takes a temp string up to which the result is created. When the index is same as the string ... Read More

Suppose we have a string J that indicates some letters that are considered as Jewel, and another string S, that represents some stones that we have. Our task is to find how many of stones in S is also jewel. The letters in J and S are case sensitive. So if the J = “aZc”, and S = “catTableZebraPicnic” then there are 7 jewels.To solve this we will convert the string into a list of characters. If the character in J present in S, then increase the count.ExampleLet us see the following implementation to get better understanding − Live Democlass Solution(object): ... Read More

We are given the array, let's say arr[] of 2n integers. We have to make the pair group of the integer elements like(a1, b1), (a2, b2)....(an, bn) which makes the sum of min(ai, bi) for all elements in the array as large as possible. The task is to find the maximum sum of pairs For example arr[] = [1, 2, 3, 4] and output is 4 the maximum sum of pairs is 4. The all possible are − (1, 2) and (3, 4) -> min(1, 2) + min(3, 4) = 1 + 3 = 4. (1, 4) and (2, 3) ... Read More

Suppose we have a binary tree; we have to compute the length of the diameter of the tree. The diameter of a binary tree is actually the length of the longest path between any two nodes in a tree. This path not necessarily pass through the root. So if the tree is like below, then the diameter will be 3.as the length of the path [4, 2, 1, 3] or [5, 2, 1, 3] is 3To solve this, we will follow these steps −We will use the dfs to find the diameter, set answer := 0call the dfs function with ... Read More

Suppose we have a non-empty string. We have to check whether it can be constructed by taking a substring of it and appending multiple times of the substring. The string consists of lowercase English letters only and its length will not exceed 10000. So if the input is like “abaabaaba”, then answer will be true, as this is created using “aba”To solve this, we will follow these steps −We will use the dynamic programming approach.Define an array DP of size n. n is the size of the stringi := 1 and j := 0while i < nif str[i] == str[j], ... Read More

Suppose we have an array of n elements. Some elements appear twice and other appear once. Elements are in range 1 0, then add i + 1 into the answerreturn the answerExampleLet us see the following implementation to get better understanding − Live Demo#include using namespace std; void print_vector(vector v){    cout

Suppose we have two arrays A and B, there are few elements in these array. We have to find the intersection of them. So if A = [1, 4, 5, 3, 6], and B = [2, 3, 5, 7, 9], then intersection will be [3, 5]To solve this, we will follow these steps −Take two arrays A and Bif length of A is smaller than length of B, then swap themcalculate the frequency of elements in the array and store them into mfor each element e in B, if e is present in m, and frequency is non-zero, decrease frequency ... Read More

Suppose in a company, one product manager is leading a team who develops a new product. Suppose latest version fails the quality check. Since each version is developed based on the previous version, all the versions after a bad version will be bad. So we have an array A with n elements [1, 2, … n] and we have to find the first bad version from this array.Consider we have a function isBadVersion(version_id), this will return whether the version is bad or not. For an example, suppose n = 5, and version = 4 is first bad version. So if ... Read More

Suppose we have a binary search tree. we have to find the Lowest common ancestor nodes of two given nodes. The LCA of two nodes p and q is actually as the lowest node in tree that has both p and q as decedent. So if the binary tree is like [6, 2, 8, 0, 4, 7, 9, null, null, 3, 5]. The tree will be like −Here LCA of 2 and 8 is 6To solve this, we will follow these steps −If the tree is empty, then return nullif p and q both are same as root, then return ... Read More