[LeetCode]#1200. Minimum Absolute Difference

Environment: Python 3.8

Key technique: if, append

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.

Analysis:

1. Sort arr.
2. st=abs(arr[1]-arr[0])
3. if st == abs(arr[i]-arr[i-1]), add to and[arr[i-1],arr[i]]
4. if st > abs(arr[i]-arr[i-1]), replace new st and ans.
5. Return ans

Solution:

class Solution:
    def minimumAbsDifference(self, arr):
        ans=[]
        arr.sort()
        st=abs(arr[1]-arr[0])
        for i in range(1,len(arr)):
            if (abs(arr[i]-arr[i-1]))==st:
                ans.append([arr[i-1],arr[i]])
            elif arr[i]-arr[i-1] < st:
                ans=[[arr[i-1],arr[i]]]
                st =arr[i]-arr[i-1]
        return ans

Submissions: