Suppose we want to design a HashMap without using any built-in hash table libraries. There will be different functions as follows −put(key, value) − This will insert a value associated with key into the HashMap. If the value already exists in the HashMap, update the value.get(key) − This will return the value to which the specified key is mapped, otherwise -1 when this map contains no mapping for the key.remove(key) − This will Remove the mapping for the value key if this map contains the mapping for the key.So, if the input is like After initialization, call the put and ... Read More

Suppose we want to design a HashSet data structure without using any built-in hash table libraries. There will be different functions like −add(x) − Inserts a value x into the HashSet.contains(x) − Checks whether the value x is present in the HashSet or not.remove(x) − Removes x from the HashSet. In case the value does not exist in the HashSet, do nothing.So, to test it Initialize the hash set, then call add(1), add(3), contains(1), contains(2), add(2), contains(2), remove(2), contains(2)., then the output will be true (1 is present), false (2 is not present), true (2 is present), false (2 is ... Read More

Suppose we want to design a class to find the kth largest element in a stream. It is the kth largest element in the sorted order, not the kth distinct element.The KthLargest class will have a constructor which accepts an integer k and an array nums, that will contain initial elements from the stream. For each call to the method KthLargest.add, will return the element representing the kth largest element in the stream.So, if the input is like k = 3, initial elements = [4, 5, 8, 2], then call add(3), add(5), add(10), add(9), add(4). , then the output will ... Read More

Suppose we have an array of non-negative integers called nums, the degree of this array is actually the maximum frequency of any one of its elements. We have to find the smallest possible length of a contiguous subarray of nums, that has the same degree as nums.So, if the input is like [1, 2, 2, 3, 1], then the output will be 2, this is because the input array has a degree of 2 because both elements 1 and 2 appear twice. The subarrays that have the same degree − [1, 2, 2, 3, 1], [1, 2, 2, 3], [2, ... Read More

Suppose we have a string s, we have to find the count of contiguous substrings that have the same number of 0's and 1's, and all the 0's and all the 1's in these substrings are grouped consecutively. If substrings occur multiple times are counted the number of times they occur.So, if the input is like "11001100", then the output will be 6, as the substrings are "1100", "10", "0011", "01", "1100", "10".To solve this, we will follow these steps −Define an array cnt of size 2 and fill this with 0res := 0for initialize i := 0, when i ... Read More

Suppose we have a positive integer, we have to check whether it has alternating bits − so, two adjacent bits will always have different values.So, if the input is like 10, then the output will be True, as binary representation of 10 is 1010.To solve this, we will follow these steps −p := n AND 1if n < 2, then −return truen := n/2while n is non-zero, do −c := n AND 1if c XOR p is same as 0, then −return falsep := cn := n/2return trueLet us see the following implementation to get better understanding −Example Live Demo#include ... Read More

Suppose we have a data structure of employee information, there are employee's unique id, his importance value and his direct subordinates' id. As an example, employee 1 is the leader of employee 2, and employee 2 is the leader of employee 3. And suppose their importance values are 15, 10 and 5, respectively. Then employee 1 has a data structure like [1, 15, [2]], and employee 2 has [2, 10, [3]], and employee 3 has [3, 5, []].So, if we have the employee information of a company, and an employee id, we have to find the total importance value of ... Read More

Suppose we have a baseball game point recorder. We have a list of strings; each string can be one of the 4 following types −Integer (one round's score) − Indicates the number of points we get in this round."+" (one round's score) − Indicates the points we get in this round are the sum of the last two valid round's points."D" (one round's score ) − Indicates the points we get in this round are the doubled data of the last valid round's points."C" (an operation, which isn't a round's score) − Indicates the last valid round's points we get ... Read More

Suppose we have an array of integers; we have to find the length of longest continuous increasing subarray.So, if the input is like [2,4,6,5,8], then the output will be 3. As the longest continuous increasing subsequence is [2,4,6], and its length is 3.To solve this, we will follow these steps −if size of nums

Suppose there is a non-empty special binary tree with some non-negative value, here each node in this tree has exactly two or zero children. If the node has two children, then this node's value is the smaller value among its two children. In other words, we can say that [root.val = minimum of root.left.val, root.right.val]. If we have such binary tree, we have to find the second minimum value in the set made of all the nodes' value in the whole tree. If there is no such element, then return -1 instead.So, if the input is likethen the output will ... Read More