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#include <iostream>
#include <message.h>
#include <teatr.h>
#include <vector>

using namespace std;

void merge(vector<int>& t, long long& b, long long& m, long long& e, long long& sum)
{
	vector<long long> wyn;
	long long i, j;

	for(i = b, j = m; i < m && j < e;)
	{

		if(t[i] <= t[j])
		{
			wyn.push_back(t[i]);
	 		++i;
		}
		else
		{
			wyn.push_back(t[j]);
			++j;
			sum += m - i;
		}
	}
	while(i < m)
	{
		wyn.push_back(t[i]);
		++i;
	}
	while(j < e)
	{
		wyn.push_back(t[j]);
		++j;
	}
	for(long long k = 0; k < e - b; k++)
	{
		t[b + k] = wyn[k];
	}
}

void merge_sort(vector<int>& t, long long b, long long e, long long& sum)
{
	if(b != e - 1)
	{
		long long mid = (b + e) / 2;
		merge_sort(t, b, mid, sum);
		merge_sort(t, mid, e, sum);
		merge(t, b, mid, e, sum);
	}
}

int main()
{
	if(!MyNodeId())
	{
		vector<int> t;
		int n = GetN();
		for(int i = 0; i < n; i++)
		{
		  int a = GetElement(i);
		  t.push_back(a);
		}
		long long sum = 0;
		long long e = t.size();
		long long b = 0;
		merge_sort(t, b, e, sum);
		cout << sum << endl;
	}
}