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 Java (OpenJDK 11.0.6) (judge verdict: Accepted)

//  ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿>
//  ⣿         
//  ⣿ Author - midu_01
//  ⣿         
//  ⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿⣿>

import java.io.*;
import java.util.*;
import java.math.*;
import java.lang.*;

public class Main
{
    static Scanner cin = new Scanner(System.in);
    static PrintStream cout = new PrintStream
    (new FileOutputStream(FileDescriptor.out));
    
    public static void main(String args[])
    {
        int t,n,m,a,b,c,d,e,i,j,k,x,y,z,/*cnt=0,*/cnt1=0;
        Vector<Integer> v = new Vector<>();
        boolean flag = false;
        n=cin.nextInt();
        int[] ch=new int[n];
        for(i=0;i<n;i++)
        {
            ch[i]=cin.nextInt();
        }
        long cnt=0;
        for(i=0;i<n;i++)
        {
            a=ch[i];
            for(j=i+1;j<n;j++)
            {
                b=ch[j];
                if(a==b) continue;
                for(k=j+1;k<n;k++)
                {
                    c=ch[k];

                    if(a==c || b==c) continue;
                    if(a+b<=c || a+c<=b || b+c<=a) continue;
                    cnt++;
                }
            }
        }
        cout.println(cnt);
    }
}