leetcode 2367. Number of Arithmetic Triplets

https://leetcode.com/problems/number-of-arithmetic-triplets/description/

 

class Solution:
    def arithmeticTriplets(self, nums: List[int], diff: int) -> int:
        answer = 0
        for i in range(len(nums)-2):
            for j in range(i+1,len(nums)-1):
                for k in range(j+1,len(nums)):
                    if nums[j] - nums[i] == diff and nums[k] - nums[j] == diff:
                        answer+=1
        return answer