Problem:
Score : 200 points

Problem Statement

We have sticks numbered 1, \cdots, N. The length of Stick i (1 \leq i \leq N) is L_i.

In how many ways can we choose three of the sticks with different lengths that can form a triangle?

That is, find the number of triples of integers (i, j, k) (1 \leq i < j < k \leq N) that satisfy both of the following conditions:

L_i, L_j, and L_k are all different.

There exists a triangle whose sides have lengths L_i, L_j, and L_k.

Constraints

1 \leq N \leq 100

1 \leq L_i \leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
L_1 L_2 \cdots L_N

Output

Print the number of ways to choose three of the sticks with different lengths that can form a triangle.

Sample Input 1

5
4 4 9 7 5

Sample Output 1

5

The following five triples (i, j, k) satisfy the conditions: (1, 3, 4), (1, 4, 5), (2, 3, 4), (2, 4, 5), and (3, 4, 5).

Sample Input 2

6
4 5 4 3 3 5

Sample Output 2

8

We have two sticks for each of the lengths 3, 4, and 5. To satisfy the first condition, we have to choose one from each length.

There is a triangle whose sides have lengths 3, 4, and 5, so we have 2 ^ 3 = 8 triples (i, j, k) that satisfy the conditions.

Sample Input 3

10
9 4 6 1 9 6 10 6 6 8

Sample Output 3

39

Sample Input 4

2
1 1

Sample Output 4

0

No triple (i, j, k) satisfies 1 \leq i < j < k \leq N, so we should print 0.

Solution in Python (3.8.2) (judge verdict: Accepted)

N = int(input())
L_list = list(map(int,input().split()))
count = 0
a = 1

for j, b in enumerate(L_list):
    if b == 1:
        continue
    for k, c in enumerate(L_list):
        if c == 1 or c == b:
            continue
        elif (a+b) > c and (b+c) > a and (c+a) > b and a < b < c:
            count += 1


for i, a in enumerate(L_list):
    if a == 1:
        continue
    for j, b in enumerate(L_list):
        if b == 1 or b == a:
            continue
        for k, c in enumerate(L_list):
            if c == 1 or c == b or c == a:
                continue
            elif (a+b) > c and (b+c) > a and (c+a) > b and a < b < c:
                count += 1

print(count)