LeetCode-in-Java

1534. Count Good Triplets

Easy

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:

Where |x| denotes the absolute value of x.

Return the number of good triplets.

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:

Solution

public class Solution {
    public int countGoodTriplets(int[] arr, int a, int b, int c) {
        int count = 0;
        for (int i = 0; i < (arr.length) - 2; i++) {
            for (int j = i + 1; j < (arr.length) - 1; j++) {
                if (Math.abs(arr[i] - arr[j]) <= a) {
                    for (int k = j + 1; k < arr.length; k++) {
                        if (Math.abs(arr[j] - arr[k]) <= b && Math.abs(arr[i] - arr[k]) <= c) {
                            count++;
                        }
                    }
                }
            }
        }
        return count;
    }
}