Package g0801_0900.s0845_longest_mountain_in_array

Class Solution

java.lang.Object

g0801_0900.s0845_longest_mountain_in_array.Solution

public class Solution
extends Object

845 - Longest Mountain in Array.<p>Medium</p> <p>You may recall that an array <code>arr</code> is a <strong>mountain array</strong> if and only if:</p> <ul> <li><code>arr.length >= 3</code></li> <li>There exists some index <code>i</code> ( <strong>0-indexed</strong> ) with <code>0 < i < arr.length - 1</code> such that: <ul> <li><code>arr[0] < arr[1] < ... < arr[i - 1] < arr[i]</code></li> <li><code>arr[i] > arr[i + 1] > ... > arr[arr.length - 1]</code></li> </ul> </li> </ul> <p>Given an integer array <code>arr</code>, return <em>the length of the longest subarray, which is a mountain</em>. Return <code>0</code> if there is no mountain subarray.</p> <p><strong>Example 1:</strong></p> <p><strong>Input:</strong> arr = [2,1,4,7,3,2,5]</p> <p><strong>Output:</strong> 5</p> <p><strong>Explanation:</strong> The largest mountain is [1,4,7,3,2] which has length 5.</p> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> arr = [2,2,2]</p> <p><strong>Output:</strong> 0</p> <p><strong>Explanation:</strong> There is no mountain.</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= arr.length <= 10⁴</code></li> <li><code>0 <= arr[i] <= 10⁴</code></li> </ul> <p><strong>Follow up:</strong></p> <ul> <li>Can you solve it using only one pass?</li> <li>Can you solve it in <code>O(1)</code> space?</li> </ul>

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	longestMountain(int[] arr)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

longestMountain

public int longestMountain(int[] arr)