Package g1201_1300.s1218_longest_arithmetic_subsequence_of_given_difference

Class Solution

java.lang.Object

g1201_1300.s1218_longest_arithmetic_subsequence_of_given_difference.Solution

public class Solution
extends Object

1218 - Longest Arithmetic Subsequence of Given Difference.<p>Medium</p> <p>Given an integer array <code>arr</code> and an integer <code>difference</code>, return the length of the longest subsequence in <code>arr</code> which is an arithmetic sequence such that the difference between adjacent elements in the subsequence equals <code>difference</code>.</p> <p>A <strong>subsequence</strong> is a sequence that can be derived from <code>arr</code> by deleting some or no elements without changing the order of the remaining elements.</p> <p><strong>Example 1:</strong></p> <p><strong>Input:</strong> arr = [1,2,3,4], difference = 1</p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong> The longest arithmetic subsequence is [1,2,3,4].</p> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> arr = [1,3,5,7], difference = 1</p> <p><strong>Output:</strong> 1</p> <p><strong>Explanation:</strong> The longest arithmetic subsequence is any single element.</p> <p><strong>Example 3:</strong></p> <p><strong>Input:</strong> arr = [1,5,7,8,5,3,4,2,1], difference = -2</p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong> The longest arithmetic subsequence is [7,5,3,1].</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 <= arr.length <= 10⁵</code></li> <li><code>-10⁴ <= arr[i], difference <= 10⁴</code></li> </ul>

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	longestSubsequence(int[] arr, int difference)

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

longestSubsequence

public int longestSubsequence(int[] arr,
 int difference)