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Monotonic Array

Problem Statement​

An array is monotonic if it is either monotone increasing or monotone decreasing.

An array nums is monotone increasing if for all i <= j, nums[i] <= nums[j]. An array nums is monotone decreasing if for all i <= j, nums[i] >= nums[j].

Given an integer array nums, return true if the given array is monotonic, or false otherwise.

Leetcode Link

Example 1:​

Input: nums = [1,2,2,3]
Output: true

Example 2:​

Input: s = "a", t = "a"
Output: "a"

Example 3:​

Input: nums = [1,3,2]
Output: false

Constraints:​

  • 1 <= nums.length <= 105
  • -105 <= nums[i] <= 105

Code​

Python Code
class Solution:
    def isMonotonic(self, A):
        return all(A[i] <= A[i - 1] for i in range(1, len(A))) or all(A[i] >= A[i - 1] for i in range(1, len(A)))