Count Good Triplets

Difficulty: Easy

Topics:
Array, Brute Force

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Problem Statement

Given an array of integers arr, and three integers a, b, and c. You need to find the number of good triplets.

A triplet (arr[i], arr[j], arr[k]) is good if the following conditions are true:

• 0 <= i < j < k < arr.length
• |arr[i] - arr[j]| <= a
• |arr[j] - arr[k]| <= b
• |arr[i] - arr[k]| <= c

Where |x| denotes the absolute value of x.

Return the number of good triplets.

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Example 1

Input: arr = [3,0,1,1,9,7], a = 7, b = 2, c = 3 Output: 4 Explanation: There are 4 good triplets: [(3,0,1), (3,0,1), (3,1,1), (0,1,1)].

Example 2

Input: arr = [1,1,2,2,3], a = 0, b = 0, c = 1 Output: 0 Explanation: No triplet satisfies all conditions.

Constraints

$$3 \le \text{arr.length} \le 100$$ $$0 \le \text{arr}[i] \le 1000$$ $$0 \le a,\, b,\, c \le 1000$$