1027.longest-arithmetic-subsequence.py

#
# @lc app=leetcode id=1027 lang=python3
#
# [1027] Longest Arithmetic Subsequence
#
# Difficulty: Medium
# Frequency: 57.5%
# Tags: Array, Hash Table, Binary Search, Dynamic Programming
# URL: https://leetcode.com/problems/longest-arithmetic-subsequence/
#
# --- Problem Description ---
#
# Given an array nums of integers, return the length of the longest arithmetic
# subsequence in nums.
#
# Note that:
#
#           - A subsequence is an array that can be derived from another array
# by deleting some or no elements without changing the order of the remaining
# elements.
#           - A sequence seq is arithmetic if seq[i + 1] - seq[i] are all the
# same value (for 0 <= i < seq.length - 1).
#
#
#
# Example 1:
#
# Input: nums = [3,6,9,12]
# Output: 4
# Explanation:  The whole array is an arithmetic sequence with steps of length
# = 3.
#
# Example 2:
#
# Input: nums = [9,4,7,2,10]
# Output: 3
# Explanation:  The longest arithmetic subsequence is [4,7,10].
#
# Example 3:
#
# Input: nums = [20,1,15,3,10,5,8]
# Output: 4
# Explanation:  The longest arithmetic subsequence is [20,15,10,5].
#
#
#
# Constraints:
#
# 	  - 2 <= nums.length <= 1000
# 	  - 0 <= nums[i] <= 500
#

#
# --- Community Solutions ---
#
# https://leetcode.com/problems/longest-arithmetic-subsequence/solutions
#

# @lc code=start
class Solution:
    def longestArithSeqLength(self, nums: List[int]) -> int:
        

# @lc code=end