Leetcode 1534. Count Good Triplets

Seawolf

1. Given an array of integers arr, and three integers a, b and c. You need to find the number of good triplets.
   
2. 
   
3. A triplet (arr[i], arr[j], arr[k]) is good if the following conditions are true:
   
4. 
   
5. 0 <= i < j < k < arr.length
   
6. |arr[i] - arr[j]| <= a
   
7. |arr[j] - arr[k]| <= b
   
8. |arr[i] - arr[k]| <= c
   
9. Where |x| denotes the absolute value of x.
   
10. 
    
11. Return the number of good triplets.
    
12. 
    
13. 
    
14. 
    
15. Example 1:
    
16. 
    
17. Input: arr = [3,0,1,1,9,7], a = 7, b = 2, c = 3
    
18. Output: 4
    
19. Explanation: There are 4 good triplets: [(3,0,1), (3,0,1), (3,1,1), (0,1,1)].
    
20. Example 2:
    
21. 
    
22. Input: arr = [1,1,2,2,3], a = 0, b = 0, c = 1
    
23. Output: 0
    
24. Explanation: No triplet satisfies all conditions.
    
25. 
    
26. 
    
27. Constraints:
    
28. 
    
29. 3 <= arr.length <= 100
    
30. 0 <= arr[i] <= 1000
    
31. 0 <= a, b, c <= 1000

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1. class Solution:
   
2.     def countGoodTriplets(self, arr: List[int], a: int, b: int, c: int) -> int:
   
3.         result = []
   
4.         for i in range(len(arr)):
   
5.             for j in range(i + 1, len(arr)):
   
6.                 for k in range(j + 1, len(arr)):
   
7.                     f = arr[i]
   
8.                     s = arr[j]
   
9.                     t = arr[k]
   
10.                     if abs(f - s) <= a and abs(s - t) <= b and abs(f - t) <= c:
    
11.                         result.append((f, s, t))
    
12.         return len(result)

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