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#include <iostream>
#include "message.h"
#include "teatr.h"
using namespace std;
long long merge(int arr[], int temp[], int left, int mid, int right) {
    int i, j, k;
    long long inv_count = 0;
    i = left;
    j = mid;
    k = left;
    while((i <= mid - 1) && (j <= right)) {
        if(arr[i] <= arr[j]) {
            temp[k++] = arr[i++];
        }
        else {
            temp[k++] = arr[j++];
            inv_count = inv_count + (mid - i);
        }
    }
    while(i <= mid - 1) {
        temp[k++] = arr[i++];
    }
    while(j <= right) {
        temp[k++] = arr[j++];
    }
    for(i = left; i <= right; i++) {
        arr[i] = temp[i];
    }
    return inv_count;
}
long long mergeSort(int arr[], int temp[], int left, int right) {
    int mid;
    long long inv_count = 0;
    if(right > left) {
        mid = (right + left) / 2;
        inv_count = mergeSort(arr, temp, left, mid);
        inv_count += mergeSort(arr, temp, mid + 1, right);
        inv_count += merge(arr, temp, left, mid + 1, right);
    }
    return inv_count;
}
int main() {
    if(MyNodeId() == 0) {
        int n = GetN(), i;
        int* t = new int[n];
        int* temp = new int[n];
        for(i = 0; i < n; i++) {
            t[i] = GetElement(i);
        }
        cout << mergeSort(t, temp, 0, n - 1) << "\n";
    }
    return 0;
}