1200.py

'''
Given an array of distinct integers arr, find all pairs of elements with the minimum absolute difference of any two elements. 

Return a list of pairs in ascending order(with respect to pairs), each pair [a, b] follows

a, b are from arr
a < b
b - a equals to the minimum absolute difference of any two elements in arr
 

Example 1:

Input: arr = [4,2,1,3]
Output: [[1,2],[2,3],[3,4]]
Explanation: The minimum absolute difference is 1. List all pairs with difference equal to 1 in ascending order.
Example 2:

Input: arr = [1,3,6,10,15]
Output: [[1,3]]
Example 3:

Input: arr = [3,8,-10,23,19,-4,-14,27]
Output: [[-14,-10],[19,23],[23,27]]
 

Constraints:

2 <= arr.length <= 10^5
-10^6 <= arr[i] <= 10^6
'''

class Solution(object):
    def minimumAbsDifference(self, arr):
        """
        :type arr: List[int]
        :rtype: List[List[int]]
        """
        if not arr:
            return []
        
        arr.sort()
        mindiff = arr[1] - arr[0]
        for index in range(2, len(arr)):
            mindiff = min(mindiff, (arr[index] - arr[index-1]))
        
        result = []
        for index in range(1, len(arr)):
            if arr[index] - arr[index-1] == mindiff:
                result.append([arr[index-1], arr[index]])
        return result