Problem Statement Reverse Integer LeetCode Solution says that – Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-231, 231 – 1], then return 0. Assume the environment does not allow you to store 64-bit integers (signed or unsigned). Example 1: …
Problem Statement Find K Closest Elements LeetCode Solution – Given a sorted integer array arr, two integers k and x, return the k closest integers to x in the array. The result should also be sorted in ascending order. An integer a is closer to x than an integer b if: |a – x| < |b – x|, or |a – x| == |b – …
Problem Statement Sort Colors LeetCode Solution – Given an array nums with n objects colored red, white, or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white, and blue. We will use the integers 0, 1, and 2 to represent the color red, white, and blue, respectively. …
Problem Statement Excel Sheet Column Number LeetCode Solution says that Given a string columnTitle that represents the column title as appears in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 … Z -> 26 AA -> 27 AB -> 28 … …
Problem Statement Range Sum Query 2D – Immutable LeetCode Solution – Given a 2D matrix, handle multiple queries of the following type: Calculate the sum of the elements of the matrix inside the rectangle defined by its upper left corner (row1, col1) and lower right corner (row2, col2). Implement the NumMatrix class: NumMatrix(int[][] …
Problem Statement Palindrome Number LeetCode Solution says that – Given an integer x, return true if x is palindrome integer. An integer is a palindrome when it reads the same backward as forward. For example, 121 is a palindrome while 123 is not. Example 1: Input: x = 121 Output: true Explanation: 121 reads as 121 from left to right …
Problem Statement Vertical Order Traversal of Binary Tree LeetCode Solution says – Given the root of a binary tree, calculate the vertical order traversal of the binary tree. For each node at position (row, col), its left and right children will be at positions (row + 1, col – 1) and (row + 1, col + 1) respectively. …
Problem Statement: Valid Triangle Number LeetCode Solution says – Given an integer array nums, return the number of triplets chosen from the array that can make triangles if we take them as side lengths of a triangle. Example 1: Input: nums = [2,2,3,4] Output: 3 Explanation: Valid combinations are: 2,3,4 (using …
Problem Statement Shortest Unsorted Continuous Subarray LeetCode Solution says that – Given an integer array nums, you have to find one continuous subarray that if you only sort this subarray in ascending order, then the whole array will be sorted in ascending order. Return the length of the shortest subarray. Example 1: …
Problem Statement: Rectangle Overlap LeetCode Solution – says that An axis-aligned rectangle is represented as a list, [x1, y1, x2, y2], where (x1, y1) is the coordinate of its bottom-left corner, and (x2, y2) is the coordinate of its top-right corner. Its top and bottom edges are parallel to the X-axis, and its left …