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Suppose we have a string containing only 4 kinds of characters 'Q', 'W', 'E' and 'R'. A string will be balanced if each of its characters appears n/4 times where n is the length of the string. Find the minimum length of the substring that can be replaced with any other string of the same length to make the original string is balanced. So if s = “QQWE”, then output will be 1. This is because we can replace Q to R, so that “RQWE”, that is balanced.Return 0 if the string is already balanced.To solve this, we will follow ... Read More
Suppose we have an array of strings products and a string called searchWord. We want to design a module that suggests at most three product names from products list after each character of searchWord is typed. The suggested products should have common prefix with the searchWord. When there are more than three products with a common prefix return the three lexicographically minimums products. So we have to find the lists of the suggested products after each character of searchWord is typed.If the input is like: [ "mobile", "mouse", "moneypot", "monitor", "mousepad"], and the searchWord is “mouse”, then the output will ... Read More
Suppose we have a binary tree. The rules of that tree is as follows −root.val == 0If treeNode.val is x and treeNode.left is not null, then treeNode.left.val = 2 * x + 1If treeNode.val is x and treeNode.right is not null, then treeNode.right.val = 2 * x + 2Now as the binary tree is contaminated. This indicates all val of the tree node have been changed to -1. We have to first recover the binary tree and then implement the FindElements class as follows −FindElements(TreeNode* root) Initializes the object with a contamined binary tree, we have to recover it first.bool ... Read More
JShell is a REPL (Read-Evaluate-Print-Loop) tool used to execute simple statements, evaluates it, and displays the result without a main() method. We can start it by simply type "jshell" in command-line prompt.We need to get the system properties by using System.getProperty() and System.getProperties() methods.In the below code snippet, we can able to display the system properties in the JShell tool by using static method property() of System class.Snippet-1jshell> System.getProperty("java.class.path") $1 ==> "C:\Program Files\Java\jdk-9.0.4\lib;C:\json-jars\json.jar;.;C:\json-jars\json-simple.jar;.;C:\json-jars\gson.jar;.;C:\json-jars\commons-io.jar;.;C:\json-jars\jackson-core.jar;.;C:\json-jars\jackson-databind.jar;.;C:\json-jars\jackson-annotations.jar;.;C:\json jars\flexjson.jar;.;C:\json-jars\jackson-dataformat-xml.jar;.;C:\json-jars\stax2-api.jar;.;C:\json-jars\jackson-dataformat-csv.jar;.;C:\json-jars\javax.json.jar;.;C:\json jars\javax.json-api.jar;.;C:\json-jars\jackson-module-jsonSchema.jar;.;C:\json-jars\json-lib.jar;.;C:\json-jars\commons-lang.jar;.;C:\json-jars\commons-logging.jar;.;"In the below code snippet, we have to use the “properties” object that extends Hashtable. So all properties can be listed as key/value pairs in the JShell tool by using ... Read More
Suppose we have a string s of '(' , ')' and lowercase English characters. We have to remove the minimum number of parentheses ( '(' or ')', in any positions ) so that the resulting parenthese string is valid and return any valid string. A parentheses string is valid when all of these criteria are fulfilled −It is the empty string, contains lowercase characters only, orIt can be written as the form of AB (A concatenated with B), where A and B are valid strings, orIt can be written as the form of (A), where A is a valid string.So ... Read More
Suppose we have a 2D grid consists of 0s (as land) and 1s (as water). An island is a maximal 4- directionally connected group of 0s. A closed island is an island totally surrounded by 1s. We have to find the number of closed islands. So if the grid is like1111111010000110101011101000010111111110So the output will be 2. There are two islands, that are completely surrounded by water.To solve this, we will follow these steps −Define a variable flagDefine a method called dfs, this will take the grid, i, j, n and mif i and j are not inside the range of ... Read More
Suppose we have a string, that string is a valid parentheses string (denoted VPS) if and only if it consists of "(" and ")" characters only, and it satisfies these properties −It is the empty string, orIt can be written as AB, where A and B are VPS's, orIt can be written as (A), where A is a VPS.We can also define the nesting depth depth(S) of any VPS S like below −depth("") = 0depth(A + B) = max of depth(A), depth(B), where A and B are VPS'sdepth("(" + A + ")") = 1 + depth(A), where A is a ... Read More
Suppose we have an N by N square grid, there each cell is either empty (0) or blocked (1). A clear path from top-left to bottom-right has length k if and only if it is composed of cells C_1, C_2, ..., C_k such that −Adjacent cells C_i and C_{i+1} are connected 8-directionally (So they are different and share an edge or corner)C_1 is at location (0, 0)C_k is at location (N-1, N-1)If C_i is located at (r, c), then grid[r, c] is empty or contains 0We have to find the length of the shortest such clear path from top-left to ... Read More
Suppose a bookstore owner has a store open for number of customers list entries minutes. In every minute, some number of customers (customers[i]) enter the store, after that all those customers leave after the end of that minute. On some minutes, the owner is grumpy. Now if the owner is grumpy on the i-th minute, then grumpy[i] = 1, otherwise grumpy[i] = 0. When the bookstore owner is grumpy, the customers of that minute are unhappy, otherwise they are happy. The bookstore owner knows a technique to keep themselves not grumpy for X minutes straight. That technique cannot be used ... Read More
Suppose we have the root of a binary tree, we have to find the maximum value V for which there exists different nodes A and B where V = |value of A – value of B| and A is an ancestor of B. So if the tree is like −Then the output will be 7. The ancestor node differences are like [(8 - 3), (7 - 3), (8 - 1), (10-13)], among them the (8 - 1) = 7 is the maximum.To solve this, we will follow these steps −initially define ans 0define one method called solve(), this will take ... Read More