Valid Triangle Number
Given an integer array nums, return the number of triplets chosen from the array that can make triangles if we take them as side lengths of a triangle.
Example 1
Input
nums = [2,2,3,4]Output
3Valid combinations are 2,3,4 using the first 2; 2,3,4 using the second 2; and 2,2,3.
Example 2
Input
nums = [4,2,3,4]Output
4There are 4 triplets that can form valid triangles.
Constraints
- 1 <= nums.length <= 1000
- 0 <= nums[i] <= 1000