1534. Count Good Triplets LeetCode Solution

In this guide, you will get 1534. Count Good Triplets LeetCode Solution with the best time and space complexity. The solution to Count Good Triplets problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.

Problem Statement
Complexity Analysis
Count Good Triplets solution in C++
Count Good Triplets solution in Java
Count Good Triplets solution in Python
Additional Resources

1534. Count Good Triplets LeetCode Solution image

Problem Statement of Count Good Triplets

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.

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 <= arr.length <= 100
0 <= arr[i] <= 1000
0 <= a, b, c <= 1000

Complexity Analysis

Time Complexity: O(n^3)
Space Complexity: O(1)

1534. Count Good Triplets LeetCode Solution in C++

class Solution {
 public:
  int countGoodTriplets(vector<int>& arr, int a, int b, int c) {
    int ans = 0;
    for (int i = 0; i < arr.size(); ++i)
      for (int j = i + 1; j < arr.size(); ++j)
        for (int k = j + 1; k < arr.size(); ++k)
          if (abs(arr[i] - arr[j]) <= a &&  //
              abs(arr[j] - arr[k]) <= b &&  //
              abs(arr[i] - arr[k]) <= c)
            ++ans;
    return ans;
  }
};
/* code provided by PROGIEZ */

1534. Count Good Triplets LeetCode Solution in Java

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

1534. Count Good Triplets LeetCode Solution in Python

class Solution:
  def countGoodTriplets(self, arr: list[int], a: int, b: int, c: int) -> int:
    return sum(abs(arr[i] - arr[j]) <= a and
               abs(arr[j] - arr[k]) <= b and
               abs(arr[i] - arr[k]) <= c
               for i in range(len(arr))
               for j in range(i + 1, len(arr))
               for k in range(j + 1, len(arr)))
 # code by PROGIEZ