Leetcode 1534: Count Good Triplets

In this Leetcode problem, we need to return all the triplets satisfying particular conditions.

Problem statement

Solution

For this problem, we can simply use brute force and try all the potential triplets with i < j < k.

We use abs for absolute value to find if the triplets satisfy the conditions.

class Solution {
public:
  int countGoodTriplets(vector<int>& arr, int a, int b, int c) {
    int res = 0;
    int l = arr.size();
    for (int i = 0; i < l; i++) {
      for (int j = i + 1; j < l; j++) {
        if (abs(arr[i] - arr[j]) > a) {
          continue;
        }
        for (int k = j + 1; k < l; k++) {
          if (abs(arr[i] - arr[k]) <= c 
              && abs(arr[j] - arr[k]) <= b) {
            res++;
          }
        }
      }
    }
    return res;
  }
};