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: Wrong Answer)



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

public class Main
{
    public static void main (String[] args)
    {
        // your code goes here
        Scanner s = new Scanner(System.in);
        int n = s.nextInt();
        int[] a = new int[n];
        for(int j=0; j<n ;j++)
        {
            a[j] = s.nextInt();
        }
        int x = 0;
        int y = 0;
        int c = 0;
        for(int i=0; i<n-2; i++)
        {
            x = a[i];
            for(int j=i+1; j<n-1; j++)
            {
                if(a[j]!=a[i])
                {
                    y = a[j];
                    int sum = x+y;
                    for(int k = j+1; k<n; k++)
                    {
                        if(a[k]!=x&&a[k]!=y&&sum>a[k])
                            c++;
                    }
                }
                else
                    break;
            }
        }
        System.out.println(c);
    }
}