Tag: Leetcode

Problem Statement This problem is from Leetcode – Arranging Coins. The problem statement in short is as below: Given n coins, return the number of complete rows in a staircase where the ith row has i coins. Solution This problem is easy enough. In awhile loop simply keep subtracting the row count from coins left. […]

Problem Statement This problem is from Leetcode – Number of Segments in a String. The problem statement is given below: Given a string, return the number of segments separated by spaces. Solution Approach – 1 We can simply use a StringTokenizer to solve this problem. See the code sample below: You can checkout the code […]

Problem Statement This problem is from Leetcode – Third Maximum Number. The problem statement is as below: Given an integer array nums, return the third distinct maximum number in this array. If the third maximum does not exist, return the maximum number. Solution Let find the max value first by looping through the array. Now […]

Problem Statement This problem is from Leetcode – Reverse Integer. The problem statement in short is given below: Given a signed 32-bit integer x, return its digits reversed. If the reversed integer overflows the 32-bit signed integer range, return 0. Solution Approach – 1 We need to extract individual numbers out of the given input […]

Problem Statement This problem is from Leetcode – Median of Two Sorted Arrays. The problem statement is given below: Given two sorted arrays of sizes m and n, return the median of the combined sorted array. Solution Approach – 1 Lets try a simple solution first. We can simply add elements from first and second […]

Problem Statement This problem is from Leetcode – Longest Substring Without Repeating Characters. The problem statement is as below: Given a string s, find the length of the longest substring without repeating characters. Solution Approach – 1 As the window is moving right, keep computing max sub-string length in a max variable. When the for […]

Problem Statement This problem is from Leetcode – Missing Number. The problem statement is as below: Given an array nums of n distinct numbers from the range [0, n], return the single number in that range that is missing from the array. Solution Approach-1 Lets try a simple for loop approach first. See the code […]

Problem statement This problem is from Leetcode – Contains Duplicate. Problem statement is given below: Given an integer array nums, return true if any value appears at least twice, otherwise return false. Solution Approach-1 Lets try a simple nested for loops approach. For each integer iterate the rest of the array to check whether another […]

Problem Statement This problem is from Leetcode – Majority Element. Given an array nums, return the element that appears more than half the time. Assume such an element always exists. Solution This problem can easily be solved by pushing the integers in the given array into a Hashmap and keeping a count of how many […]

Problem Statement This problem is from Leetcode – Single Number. The problem statement is as below: Given an integer array where every element appears twice except one, find the single element that appears only once. Solution This problem is asking us to figure out that one integer that isn’t repeating. Lets take the Hashmap approach […]

Problem Statement This problem is from Leetcode – Valid Palindrome. The problem statement in short is as below: Given a string s, return true if it is a palindrome after converting to lowercase and removing all non-alphanumeric characters; otherwise, return false. Solution This problem is asking us to check whether the given string is a […]

Problem Statement This problem is from Leetcode – Merge Sorted Array. The problem statement in short is as below: Merge two sorted arrays nums1 and nums2 into nums1 in-place. nums1 has length m + n with the first m elements valid; nums2 has length n. Solution Approach-1 See the code sample below: You can check […]

Problem Statement This problem is from Leetcode – Length of Last Word. The problem statement is as below: Given a string s consisting of words and spaces, return the length of the last word in the string Solution Approach-1 Lets try the most obvious approach first, by using split() Lets see the code sample below: […]

Problem Statement This problem is from Leetcode – Search Insert Position. The problem statement is given below: Given a sorted array and a target, return the target’s index or the insertion index if not found. Solution This problem is asking us to figure out the correct index position for a given number in a sorted […]

Problem Statement This problem is from Leetcode – Best Time to Buy and Sell Stock. The problem statement in short is as below: Given stock prices, find the max profit from one buy-sell transaction. Return 0 if no profit. Solution This problem is asking us to figure out that as we are moving forward in […]