#include <bits/stdc++.h>
using namespace std;

int N;

const int MAX_N = 30000;
vector<int> X( MAX_N );

const int DEC = 200;
const int MAX_Y = MAX_N / DEC + 1;
vector<int> Y( MAX_Y );

void Add( int iNum )
{
	X[ iNum ]++;
	Y[ iNum / DEC ]++;
}
int Sum( int iL, int iR )
{
int i;
int iStart;
int iEnd;
int iSum;

	iStart	= 1 + ( iL - 1 ) / DEC;
	iEnd	= iR / DEC;
	iSum	= 0;
	if( iStart < iEnd )
	{
		iSum = accumulate( &Y[ iStart ], &Y[ iEnd ], iSum );
		iSum = accumulate( &X[ iL ], &X[ iStart * DEC ], iSum );
		iSum = accumulate( &X[ iEnd * DEC ], &X[ iR ], iSum );
	}
	else
		iSum = accumulate( &X[ iL ], &X[ iR ], iSum );

	return iSum;
}

int Sum( int iL )
{
	return Sum( iL, N + 1 );
}

int main()
{
int i;
int M;
int iSum;

	ios::sync_with_stdio( false );
	cin.tie( 0 );

	cin >> N;

	iSum = 0;
	for( i = 1; i <= N; i++ )
	{
		cin >> M;

		Add( M );
		iSum += Sum( M + 1 );
	}

	cout << iSum << endl;

	return 0;
}