In Spring Boot, you can call multiple APIs in parallel and then work on the combined response using CompletableFuture and CompletableFuture.allOf(). Here’s an example of how you can achieve this: 2. Create a Controller to Trigger Parallel API Calls: Create a controller class that will trigger parallel API calls and work on the combined response….
Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it can trap after raining. Example 1: Input: height = [0,1,0,2,1,0,1,3,2,1,2,1] Output: 6 Explanation: The above elevation map (black section) is represented by array [0,1,0,2,1,0,1,3,2,1,2,1]. In this case, 6 units of rain water (blue section) are being trapped….
Given an unsorted integer array nums, return the smallest missing positive integer. You must implement an algorithm that runs in O(n) time and uses O(1) auxiliary space. Example 1:Input: nums = [1,2,0] Output: 3 Explanation: The numbers in the range [1,2] are all in the array. Example 2:Input: nums = [3,4,-1,1] Output: 2 Explanation: 1 is in the array but…
Write a program to solve a Sudoku puzzle by filling the empty cells. A sudoku solution must satisfy all of the following rules: The ‘.’ character indicates empty cells. Example 1: Input: board = [[“5″,”3″,”.”,”.”,”7″,”.”,”.”,”.”,”.”],[“6″,”.”,”.”,”1″,”9″,”5″,”.”,”.”,”.”],[“.”,”9″,”8″,”.”,”.”,”.”,”.”,”6″,”.”],[“8″,”.”,”.”,”.”,”6″,”.”,”.”,”.”,”3″],[“4″,”.”,”.”,”8″,”.”,”3″,”.”,”.”,”1″],[“7″,”.”,”.”,”.”,”2″,”.”,”.”,”.”,”6″],[“.”,”6″,”.”,”.”,”.”,”.”,”2″,”8″,”.”],[“.”,”.”,”.”,”4″,”1″,”9″,”.”,”.”,”5″],[“.”,”.”,”.”,”.”,”8″,”.”,”.”,”7″,”9″]] Output: [[“5″,”3″,”4″,”6″,”7″,”8″,”9″,”1″,”2”],[“6″,”7″,”2″,”1″,”9″,”5″,”3″,”4″,”8”],[“1″,”9″,”8″,”3″,”4″,”2″,”5″,”6″,”7”],[“8″,”5″,”9″,”7″,”6″,”1″,”4″,”2″,”3”],[“4″,”2″,”6″,”8″,”5″,”3″,”7″,”9″,”1”],[“7″,”1″,”3″,”9″,”2″,”4″,”8″,”5″,”6”],[“9″,”6″,”1″,”5″,”3″,”7″,”2″,”8″,”4”],[“2″,”8″,”7″,”4″,”1″,”9″,”6″,”3″,”5”],[“3″,”4″,”5″,”2″,”8″,”6″,”1″,”7″,”9”]] Explanation: The input board is shown above and the only valid solution is shown below: Constraints: Java Solution This program defines a…
Given a string containing just the characters ‘(‘ and ‘)’, return the length of the longest valid (well-formed) parentheses substring. Example 1:Input: s = “(()” Output: 2 Explanation: The longest valid parentheses substring is “()”. Example 2:Input: s = “)()())” Output: 4 Explanation: The longest valid parentheses substring is “()()”. Example 3:Input: s = “” Output: 0 Constraints: Java…
You are given a string s and an array of strings words. All the strings of words are of the same length. A concatenated substring in s is a substring that contains all the strings of any permutation of words concatenated. Return the starting indices of all the concatenated substrings in s. You can return the answer in any order. Example 1:Input: s = “barfoothefoobarman”, words = [“foo”,”bar”] Output: [0,9]…
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Given the head of a linked list, reverse the nodes of the list k at a time, and return the modified list. k is a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple of k then left-out nodes, in the end, should remain as it is. You…
If you are using the @Query annotation in your Spring Data JPA repository and you want to handle the result of a native query with three columns, you can use the Object return type directly in the method signature. Here’s an example: In this example, the findThreeColumns method is annotated with @Query, and the nativeQuery…
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Problem Statement You are given an array of k linked-lists lists, each linked-list is sorted in ascending order. Merge all the linked-lists into one sorted linked-list and return it. Example 1: Input: lists = [[1,4,5],[1,3,4],[2,6]] Output: [1,1,2,3,4,4,5,6] Explanation: The linked-lists are: [ 1->4->5, 1->3->4, 2->6 ] merging them into one sorted list: 1->1->2->3->4->4->5->6 Example 2:…
Problem Statement Given an input string s and a pattern p, implement regular expression matching with support for ‘.’ and ‘*’ where: ‘.’ Matches any single character. ‘*’ Matches zero or more of the preceding element. The matching should cover the entire input string (not partial). Example 1: Input: s = “aa”, p = “a”…
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