# Task
Given some sticks by an array `V` of positive integers, where V[i] represents the length of the sticks, find the number of ways we can choose three of them to form a triangle.
# Example
 For `V = [2, 3, 7, 4]`, the result should be `1`.
 There is only `(2, 3, 4)` can form a triangle.
 For `V = [5, 6, 7, 8]`, the result should be `4`.
 `(5, 6, 7), (5, 6, 8), (5, 7, 8), (6, 7, 8)` 
# Input/Output
 - `[input]` integer array `V`
 stick lengths
 `3 <= V.length <= 100`
 `0 < V[i] <=100`
 - `[output]` an integer
 number of ways we can choose 3 sticks to form a triangle.
from itertools import combinations
def counting_triangles(V):
    count = 0
    for i in combinations(V,3):
        i = sorted(i)
        if i[0]+i[1] > i[2]:
            count += 1
    return count
from itertools import combinations
def counting_triangles(V):
    count = 0
    for i in combinations(V,3):
        i = sorted(i)
        if i[0]+i[1] > i[2]:
            count += 1
    return count