Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.
Example 1: Input: num1 = "2", num2 = "3" Output: "6" Example 2: Input: num1 = "123", num2 =…
Given a collection of candidate numbers and a key, find all unique combinations in candidates where the candidate numbers sums to target.
Each number in candidates may only be used once in the combination. Note: • All numbers (including target) will be positive integers. • The…
Merge k sorted linked lists and return it as one sorted list in C++
Example: Input: [ 1->4->5, 1->3->4, 2->6 ] Output: 1->1->2->3->4->4->5->6 This problem can be solved by…
Given an array sorted in ascending order and is rotated at some pivot, given a target value to search, if found in the array return its index
Problem explanation: Initial Sorted array: [0,1,2,4,5,6,7] After rotation it becomes [4,5,6,7,0,1,2]. Target = 0 Index = 4 [as array index…
Implement next permutation, which rearranges numbers into the lexicographically next greater permutation of numbers.
If such arrangement is not possible, it must rearrange it as the lowest possible order (ie, sorted in ascending order). Examples: Input ->…
Given two integers dividend and divisor, divide two integers without using multiplication, division and mod operator.
Return the quotient after dividing dividend by divisor. The integer division should truncate toward zero. Example 1: Input: dividend = 10,…
Swap Nodes in Pairs solution in C
Given a linked list, swap every two adjacent nodes and return its head. Example: Given 1->2->3->4, you should return the list as…
Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.
Note: 1. Need merged elements in a new list, not in the existing list. Example: Input: 1->2->4, 1->3->4 Output:…
Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.
For example, given n = 3, a solution set is: [ "((()))", "(()())", "(())()", "()(())",…
Letter Combinations of a Phone Number
Problem statement: Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could…