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

public class Main{
	
	static long mod=(long)1e9+7;
	
	public static void main(String[] args) throws IOException {
		Writer out=new Writer(System.out);
		Reader in=new Reader(System.in);
		int ts=1;
		
		outer: while(ts-->0) {	
			int n=in.nextInt();
			int a[]=in.readArray(n);
			if(n<3) {
				out.println(0);
				continue outer;
			}
			int count=0;
			for(int i=0; i<n; i++) for(int j=i+1; j<n; j++) for(int k=j+1; k<n; k++) {
				if(a[i]!=a[j] && a[j]!=a[k] && a[i]!=a[k]) {
					int m=max(a[i],max(a[j],a[k]));
					int sum=a[i]+a[j]+a[k];
					if(2*m<sum) count++;
				}
			}
			out.println(count);
		}
		out.close();		
		
	}

	
	
/*********************************** UTILITY CODE BELOW **************************************/	
		
	static int abs(int a) {
		return a>0 ? a : -a;
	}
	
	static int max(int a, int b) {
		return a>b ? a : b;
	}
	
	static int pow(int n, int m) {
		if(m==0) return 1;
		int temp=pow(n,m/2);
		long res=(((long)temp*temp)%mod);
		if(m%2==0) return (int)res;
		return (int)((res*n)%mod);
	}
	
	static class Pair{
		int u, v;
		
		Pair(int u, int v){this.u=u; this.v=v;}
		
		static void sort(Pair [] coll) {		
			List<Pair> al=new ArrayList<>(Arrays.asList(coll));
			Collections.sort(al,new Comparator<Pair>() {
				public int compare(Pair p1, Pair p2) {
					return p1.u-p2.u;
				}	
			});
			for(int i=0; i<al.size(); i++) {
				coll[i]=al.get(i);
			}
		}
		
	}
	
	static void sort(int[] a) {
		ArrayList<Integer> list=new ArrayList<>();
		for (int i:a) list.add(i);
		Collections.sort(list);
		for (int i=0; i<a.length; i++) a[i]=list.get(i);
	}
	
	static int [] array(int n, int value) {	
		int a[]=new int[n];
		for(int i=0; i<n; i++) a[i]=value;
		return a;
	}
	
	static class Reader{
		
		BufferedReader br;
		StringTokenizer to;
		
		Reader(InputStream stream){
			br=new BufferedReader(new InputStreamReader(stream));
			to=new StringTokenizer("");
		}
		
		String next() {
			while(!to.hasMoreTokens()) {
				try {
					to=new StringTokenizer(br.readLine());	
				}catch(IOException e) {}
				
			}
			return to.nextToken();
			
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
		
		int [] readArray(int n) {
			int a[]=new int[n];
			for(int i=0; i<n ;i++) a[i]=nextInt();
			return a;
		}
		long [] readLongArray(int n) {
			long a[]=new long[n];
			for(int i=0; i<n ;i++) a[i]=nextLong();
			return a;
		}
		
	}
	
	static class Writer extends PrintWriter{
		Writer(OutputStream stream){
			super(stream);
		}
		void println(int [] array) {
			for(int i=0; i<array.length; i++) {
				print(array[i]+" ");
			}
			println();
		}
		void println(long [] array) {
			for(int i=0; i<array.length; i++) {
				print(array[i]+" ");
			}
			println();
		}
	}
	
}