Construct Binary Search Tree from Preorder Traversal, 1010. Smallest Value of the Rearranged Number, 2167. People Whose List of Favorite Companies Is Not a Subset of Another List, 1453. Problem Statement: Given a mountain array arr, return the index i such that arr[0] .. arr[1] arr[i - 1] .. arr[i] .. arr[i + 1] arr[arr.length - 1] | Java Solutionhttps://leetcode.com/problems/peak-index-in-a-mountain-arrayFind the complete playlist of LeetCode Problemshttps://www.youtube.com/watch?v=cORK0YESg9A\u0026list=PL_6klLfS1WqF1n0GbPCqk0rPDFAu1dzXC------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------Do checkout other videosJava Projects Playlist: https://www.youtube.com/watch?v=pMR_48AF-A0\u0026list=PL_6klLfS1WqE1-_MJgZiJqAaccjLGHh0HJavaScript Projects Playlist: https://www.youtube.com/playlist?list=PL_6klLfS1WqHeBjBpJba1jl04UegweWscReact Projects Playlist: https://www.youtube.com/playlist?list=PL_6klLfS1WqHM02usd5VBnc0yempce2ptMERN Stack Projects Playlist: https://www.youtube.com/playlist?list=PL_6klLfS1WqEb6YL--KRviPGYAfx7AODHSpring Boot Full Stack Projects: https://www.youtube.com/playlist?list=PL_6klLfS1WqFi9710tOEs_b3Mco-_TecRNext.js Projects Playlist: https://www.youtube.com/playlist?list=PL_6klLfS1WqGskn7Mp9HYD-xrE30pmf9rFollow UsInstagram: codeforinterview (https://instagram.com/codeforinterview)Telegram: codeforinterview (https://t.me/codeforinterview) Maximum Sum of 3 Non-Overlapping Subarrays, 702. Number of Operations to Make Network Connected, 1320. The Most Frequently Ordered Products for Each Customer, 1597. Prime Number of Set Bits in Binary Representation, 774. Construct the Lexicographically Largest Valid Sequence, 1719. length - 1] Solution: With binary search, the goal after each iteration is to eliminate, at minimum, half of the elements. Is there an equivalent of the Harvard sentences for Japanese? Repeat the above process. Longest Palindromic Substring 6. First Completely Painted Row or Column, 2662. Find Customers With Positive Revenue this Year, 1823. Paths in Maze That Lead to Same Room, 2078. Developed by JavaTpoint. Find All K-Distant Indices in an Array, 2201. A mountain array is an array of length at least 3 with elements strictly increasing from starting till an index i, and then strictly decreasing from index i to last index. Greatest English Letter in Upper and Lower Case, 2311. Check if All Characters Have Equal Number of Occurrences, 1942. Count Number of Possible Root Nodes, 2584. Find Smallest Letter Greater Than Target, 747. Minimum Operations to Make the Integer Zero, 2750. Length of Longest Fibonacci Subsequence, 889. Remove Digit From Number to Maximize Result, 2260. Lowest Common Ancestor of Deepest Leaves, 1129. Minimum ASCII Delete Sum for Two Strings, 714. Flip Binary Tree To Match Preorder Traversal, 982. K Highest Ranked Items Within a Price Range, 2147. Decrypt String from Alphabet to Integer Mapping, 1312. Number of Ways to Rearrange Sticks With K Sticks Visible, 1867. Set high=Mid, Again, find the mid of the array Mid=low+(high-low)/2, Therefore, 2 >= 7, the condition is false. Lowest Common Ancestor of a Binary Tree II, 1647. Maximum Count of Positive Integer and Negative Integer, 2530. The Employee That Worked on the Longest Task, 2433. Count Odd Numbers in an Interval Range, 1525. Customer Stories Resources Open Source GitHub Sponsors . Minimum Operations to Make Numbers Non-positive, 2710. Maximum Product of the Length of Two Palindromic Substrings, 1961. Smallest Range Covering Elements from K Lists, 659. Longest Substring of One Repeating Character, 2216. Divide Players Into Teams of Equal Skill, 2492. Choose Numbers From Two Arrays in Range, 2144. Convert Sorted List to Binary Search Tree, 116. Exit from the loop and return low i.e. Minimum Difficulty of a Job Schedule, 1339. Count the Number of Consistent Strings, 1685. )If you like this. Maximum Number of Groups With Increasing Length, 2791. A mountain sub-array consists of elements that are initially in ascending order until a peak element is reached and beyond the peak element all other elements of the sub-array are in decreasing order. Note: The generated output will always be 1 if the index that you return is correct. Minimum Increment to Make Array Unique, 947. In this post, we are going to solve the 852. Find Minimum in Rotated Sorted Array II, 158. Vertical Order Traversal of a Binary Tree, 990. Maximum XOR of Two Non-Overlapping Subtrees, 2482. At each iteration, if the current element is greater than the previous element and the current element is smaller than the next element then the current element is the peak element. Minimum Cost to Make at Least One Valid Path in a Grid, 1369. Follow the steps below to solve the problem: Initialize two variables, say ans, to store the index of the peak element of the array. if anyone can explain feel free. Count the Number of Beautiful Subarrays, 2591. Check if an Original String Exists Given Two Encoded Strings, 2061. Reorder Routes to Make All Paths Lead to the City Zero, 1467. Sum of Absolute Differences in a Sorted Array, 1687. There are four different scenarios we need to take into consideration. So, in this section, we are going to find the peak index of mountain array in Java with different approaches and logic. photo. c++ - Code to find peak index of mountain array - Stack Overflow Code to find peak index of mountain array Ask Question Asked 4 years ago Modified 4 years ago Viewed 265 times 0 You may recall that an array A is a mountain array if and only if: A.length >= 3 There exists some i with 0 < i < A.length - 1 such that: A [0] < A [1] < . Java. To achieve this, lets take a look at an example input: [3, 4, 5, 6, 7, 8, 1]. Product of Two Run-Length Encoded Arrays, 1869. Register or Sign in. Check if a Parentheses String Can Be Valid, 2117. Unique Orders and Customers Per Month, 1566. Let's implement the above approach in a Java program. Widest Vertical Area Between Two Points Containing No Points, 1638. Sum of Nodes with Even-Valued Grandparent, 1317. Number of Valid Words for Each Puzzle, 1180. Smallest Value After Replacing With Sum of Prime Factors, 2508. Thanks for contributing an answer to Stack Overflow! Find All Possible Recipes from Given Supplies, 2116. Find Maximum Number of String Pairs, 2749. Difference Between Ones and Zeros in Row and Column, 2486. An array arr a mountain if the following properties hold: Given a mountain array arr, return the index i such that arr[0] < arr[1] < < arr[i - 1] < arr[i] > arr[i + 1] > > arr[arr.length - 1]. Customers Who Bought Products A and B but Not C, 1403. Get Biggest Three Rhombus Sums in a Grid, 1880. If the midpoint is more than midpoint + 1, we will eliminate everything to the right of midpoint by moving the end pointer to the midpoint. Sum of Imbalance Numbers of All Subarrays, 2764. is Array a Preorder of Some Binary Tree, 2767. Solutions For. Maximum Number of Jumps to Reach the Last Index, 2771. It is a very interesting problem frequently asked in interviews of top IT companies like Google, Amazon, TCS, Accenture, Adobe, Apple, Infosys, etc. def peakIndexInMountainArray (self, A): lo, hi = 0, len (A) - 1 while lo < hi: mid = (lo + hi) / 2 if A [mid] < A [mid + 1]: lo = mid + 1 else: hi = mid return lo See also HackerRank Solutions - Bit Manipulation - Lonely Integer - Java Solution Design Graph With Shortest Path Calculator, 2644. Minimum Fuel Cost to Report to the Capital, 2479. Number of Subarrays Having Even Product, 2496. Conclusions from title-drafting and question-content assistance experiments Identifying peak elevation in a list of lists in Python, Peak finder in Python in O(log n) complexity. The elements in the given array must be in either ascending or descending sorted order. How feasible is a manned flight to Apophis in 2029 using Artemis or Starship? Construct Binary Tree from Preorder and Inorder Traversal, 106. Unique Length-3 Palindromic Subsequences, 1931. Count Substrings with Only One Distinct Letter, 1186. Take K of Each Character From Left and Right, 2520. 1744. Percentage of Users Attended a Contest, 1634. Number of Connected Components in an Undirected Graph, 331. Count Words Obtained After Adding a Letter, 2136. Number of Visible People in a Queue, 1945. Peak Index in a Mountain Array Solution in C++, 852. Inside the loop, the mid index is calculated as the average of start and end indices. Longest ZigZag Path in a Binary Tree, 1374. Split a String Into the Max Number of Unique Substrings, 1594. Find the Prefix Common Array of Two Arrays, 2660. Minimum Operations to Make All Array Elements Equal, 2605. Airplane Seat Assignment Probability, 1228. Flight Occupancy and Waitlist Analysis, 2786. Determine Color of a Chessboard Square, 1815. Minimum Cost to Reach Destination in Time, 1930. Maximum Enemy Forts That Can Be Captured, 2515. Making statements based on opinion; back them up with references or personal experience. Binary String With Substrings Representing 1 To N, 1026. Check If a Number Is Majority Element in a Sorted Array, 1151. Maximum Number of Accepted Invitations, 1821. Count Positions on Street With Required Brightness, 2238. Difference Between Maximum and Minimum Price Sum, 2539. Determine if String Halves Are Alike, 1707. Count Number of Rectangles Containing Each Point, 2259. Check if String Is Decomposable Into Value-Equal Substrings, 1935. Sell Diminishing-Valued Colored Balls, 1649. The Earliest Moment When Everyone Become Friends, 1104. Count All Valid Pickup and Delivery Options, 1364. Minimum Adjacent Swaps to Make a Valid Array, 2342. The Binary Search algorithm is used to find out the required element in the sorted array of elements. We have declared a variable named mid and initialized it to 0 and a variable named high which is equal to high-1. In the Linear Search approach, we will iterate through the given input array Aand at each iteration, if the current integer is greater than the previous integer and the current integer is smaller than the next integer then the current integer is the peak element. Find the Student that Will Replace the Chalk, 1896. 1746. Optimize Water Distribution in a Village, 1170. Maximum Number of Occurrences of a Substring, 1298. Number of Burgers with No Waste of Ingredients, 1277. Number of Subsequences That Satisfy the Given Sum Condition, 1502. Minimum Adjacent Swaps for K Consecutive Ones, 1704. 's to Avoid Consecutive Repeating Characters, 1577. Maximum Value of a String in an Array, 2499. Smallest Rotation with Highest Score, 801. Because the largest element in the array is 110 whose index is 3. Average Value of Even Numbers That Are Divisible by Three, 2457. Inside a while loop, we have defined a condition low < high. Number of Unequal Triplets in Array, 2476. Paths in Matrix Whose Sum Is Divisible by K, 2436. Minimum Total Cost to Make Arrays Unequal, 2503. Number of Pairs of Interchangeable Rectangles, 2002. Note that with each iteration, we are removing at least half of the remaining elements by moving the start and end pointers to the midpoint + 1 and midpoint respectively. Minimum Hours of Training to Win a Competition, 2385. Maximum Nesting Depth of the Parentheses, 1616. Minimum Cost to Move Chips to The Same Position, 1218. Not the answer you're looking for? Successful Pairs of Spells and Potions, 2302. Find a Value of a Mysterious Function Closest to Target, 1523. So one basic idea would be to scan the array from left and check strictly increasing and then decreasing order of elements. Find the Kth Largest Integer in the Array, 1986. Average Salary Excluding the Minimum and Maximum Salary, 1493. Leetcode / 852 - Peak Index in a Mountain Array.java Go to file Go to file T; Go to line L; Copy path Delete the Middle Node of a Linked List, 2096. The video has the Problem Statement, Solution Dry Run, Code for the Leetcode question 852. If A [mid-1] < A [mid] < A [mid+1], then the peak is in A [mid+1:]. Count Unreachable Pairs of Nodes in an Undirected Graph, 2320. Count Nodes Equal to Average of Subtree, 2267. Last Substring in Lexicographical Order, 1168. > arr [arr.length - 1] String to Integer (atoi) 9. Please let me know if youre still unclear on how to solve this problem! Number of Adjacent Elements With the Same Color, 2673. Number of Distinct Substrings in a String, 1699. Number of Distinct Binary Strings After Applying Operations, 2452. Binary Tree Zigzag Level Order Traversal, 105. Number of Substrings Containing All Three Characters, 1359. The mountain increases until it doesnt. Read N Characters Given read4 II - Call Multiple Times, 159. It is clear from the above examples that there is always a peak element in the input array. Determine the Winner of a Bowling Game, 2661. Longest Word in Dictionary through Deleting, 549. This tutorial is only for Educational and Learning purpose. Intervals Between Identical Elements, 2123. Orders With Maximum Quantity Above Average, 1868. Minimum Number of Increments on Subarrays to Form a Target Array, 1533. Longest Subsequence With Limited Sum, 2391. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. Repeat the 2nd and 3rd step recursively, until left is smaller than right. To eliminate elements that we havent checked, we can use binary search. How to create an overlapped colored equation? rev2023.7.21.43541. Shortest Path with Alternating Colors, 1131. Detect Pattern of Length M Repeated K or More Times, 1567. Longest Even Odd Subarray With Threshold, 2763. Find a Corresponding Node of a Binary Tree in a Clone of That Tree, 1381. Maximum Product of Splitted Binary Tree, 1342. Ways to Split Array Into Good Subarrays, 2752. Sort Array by Moving Items to Empty Space, 2461. Maximum Number of Non-Overlapping Substrings, 1521. JavaTpoint offers too many high quality services. Binary Search Tree to Greater Sum Tree, 1039. Peak Index in a Mountain Array LeetCode Solution An array arramountainif the following properties hold: Given a mountain arrayarr, return the indexisuch thatarr[0] < arr[1] < < arr[i - 1] < arr[i] > arr[i + 1] > > arr[arr.length - 1]. Number of Strings That Appear as Substrings in Word, 1968. Link to Problem: https://leetcode.com/problems/peak-index-in-a-mountain-array/. Peak Index in a Mountain ArrayPeak Index in a Mountain ArrayPeak Index in a Mountain Array SolutionLeetcode Peak Index in a Mountain ArrayPeak Index in a Mountain Array Leetcode SolutionPeak Index in a Mountain Array Java SolutionValid Mountain ArrayValid Mountain Array LeetcodeValid Mountain Array Java SolutionLeetcode 852Leetcode 852 SolutionLeetcode Solutions PlaylistLeetcode Java Solutions PlaylistLeetcode Easy SolutionsMaximum Subarray Developer Docs LeetcodeDeveloper Docs LeetcodeHashtags: #leetcode #leetcodesolution #java #javaprogramming #javatutorial #javaforbeginners #leetcodedailychallenge #dynamicprogramming Thus, we can eliminate everything to the right of the midpoint. Problem Statement: Given a mountain array arr, return the index i such that arr[0] .. arr[1] . Maximum Alternating Subsequence Sum, 1913. Minimize Rounding Error to Meet Target, 1059. Keeping with the same logic, we will compare the midpoint to the element directly to the right, 8 > 1. Minimum Sum of Four Digit Number After Splitting Digits, 2161.