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

using namespace std;

typedef long long ll;

int n;

ll Merge(vector<int>& L, vector<int>& P, vector<int>& wyn)
{
    int l = 0, p = 0;
    ll inv = 0;
    while (l < L.size() || p < P.size())
    {
        if (l < L.size() && p < P.size())
        {
            if (L[l] <= P[p])
            {
                wyn.push_back(L[l]);
                ++l;
            }
            else
            {
                wyn.push_back(P[p]);
                ++p;
                inv += L.size() - l;
            }
        }
        else
        {
            if (l < L.size())
            {
                wyn.push_back(L[l]);
                ++l;
            }
            else
            {
                wyn.push_back(P[p]);
                ++p;
            }
        }
    }
    return inv;
}

ll MergeSort(vector<int>& a, int l, int p)
{
    if (l == p)
        return 0;
    int s = (l + p) / 2;
    ll inv = MergeSort(a, l, s) + MergeSort(a, s + 1, p);
    vector<int> L, P;
    for (int i = l; i <= p; ++i)
    {
        if (i <= s)
            L.push_back(a[i]);
        else
            P.push_back(a[i]);
    }
    vector<int> wyn;
    inv += Merge(L, P, wyn);
    for (int i = 0; i < wyn.size(); ++i)
        a[i + l] = wyn[i];
    return inv;
}

int main()
{
    if (MyNodeId() != 0)
        return EXIT_SUCCESS;
    n = GetN();
    vector<int> a(n);
    for (int i = 0; i < n; ++i)
        a[i] = GetElement(i);
    cout << MergeSort(a, 0, n - 1);
    return EXIT_SUCCESS;
}