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#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

#include "message.h"
#include "teatr.h"



#define MAX 100000100
using namespace std;

int tab[10];
int buf[MAX];

unsigned long long ans = 0;

int temp[MAX];
unsigned long long merge(int arr[],int temp[],int left,int mid,int right)
{
    int i=left;
    int j=mid;
    int k=left;
    unsigned long long int invcount=0;
    while((i<=mid-1) && (j<=right))
    {
        if(arr[i]<=arr[j])
        temp[k++]=arr[i++];
        else
        {
            temp[k++]=arr[j++];
            invcount+=(mid-i);
        }
    }
    while(i<=mid-1)
    temp[k++]=arr[i++];
    while(j<=right)
    temp[k++]=arr[j++];
    for(int i=left;i<=right;i++)
    arr[i]=temp[i];
    return invcount;
}
unsigned long long int mergesort(int arr[],int temp[],int left,int right)
{
    unsigned long long int invcount=0;
    if(right>left){
        int mid=(left+right)/2;
        invcount=mergesort(arr,temp,left,mid);
        invcount+=mergesort(arr,temp,mid+1,right);
        invcount+=merge(arr,temp,left,mid+1,right);
    }
    return invcount;
}

int main() {
	if(MyNodeId() != 0) {
		return 0;
	}
	int n = GetN();
	unsigned long long res2 = 0;
	int mx = 0;
	for(int i = 0; i < n; ++i) {
		int el = GetElement(i);
		if(el > mx) {
			mx = el;
		}
		buf[i] = el;
	}
	if(mx <= 5) {
		for(int i = 0; i < n; ++i) {
			++tab[buf[i]];
			for(int j = 0; j < 10; ++j) {
				if(j > buf[i]) {
					res2 += tab[j];
				}
			}
		}
		cout << res2 << endl;
	} else {
		cout << mergesort(buf, temp, 0, n-1) << endl;
	}
	
	return 0;
}