Package g1901_2000.s1995_count_special_quadruplets

Class Solution

java.lang.Object

g1901_2000.s1995_count_special_quadruplets.Solution

public class Solution
extends Object

1995 - Count Special Quadruplets\. Easy Given a **0-indexed** integer array `nums`, return _the number of **distinct** quadruplets_ `(a, b, c, d)` _such that:_ * `nums[a] + nums[b] + nums[c] == nums[d]`, and * `a < b < c < d` **Example 1:** **Input:** nums = [1,2,3,6] **Output:** 1 **Explanation:** The only quadruplet that satisfies the requirement is (0, 1, 2, 3) because 1 + 2 + 3 == 6. **Example 2:** **Input:** nums = [3,3,6,4,5] **Output:** 0 **Explanation:** There are no such quadruplets in [3,3,6,4,5]. **Example 3:** **Input:** nums = [1,1,1,3,5] **Output:** 4 **Explanation:** The 4 quadruplets that satisfy the requirement are: - (0, 1, 2, 3): 1 + 1 + 1 == 3 - (0, 1, 3, 4): 1 + 1 + 3 == 5 - (0, 2, 3, 4): 1 + 1 + 3 == 5 - (1, 2, 3, 4): 1 + 1 + 3 == 5 **Constraints:** * `4 <= nums.length <= 50` * `1 <= nums[i] <= 100`

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	countQuadruplets(int[] nums)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

countQuadruplets

public int countQuadruplets(int[] nums)