1534. Count Good Triplets
阿新 • • 發佈:2020-08-03
Given an array of integersarr
, and three integersa
,b
andc
. You need to find the number of good triplets.
A triplet(arr[i], arr[j], arr[k])
isgoodif 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|
x
.
Returnthe 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
class Solution { public int countGoodTriplets(int[] arr, int a, int b, int c) { int res = 0; for(int i = 0; i < arr.length - 2; i++) { for(int j = i + 1; j < arr.length - 1; 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) res++; } } } return res; } }
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