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#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("inv.in");
ofstream fout("inv.out");
int v[100001], arb[400001],i,j,n,x,pos,answ,start,finish;
struct cub
{
int val;
int poz;
}a[100002];
int cmp(cub o, cub p)
{
return o.val<p.val;
}
void update(int nod, int st, int dr)
{
if(st==dr)
{
arb[nod]++;
return;
}
int mid=(st+dr)/2;
if(pos<=mid)
update(nod*2,st,mid);
else
update(nod*2+1,mid+1,dr);
arb[nod]++;
}
void query (int nod, int st, int dr)
{
if (st>=start&&dr<=finish)
{
answ+=arb[nod];
return;
}
int mid=(st+dr)/2;
if(start<=mid)
query(nod*2,st,mid);
if(mid<finish)
query(nod*2+1,mid+1,dr);
}
int main()
{
fin >>n;
for(i=1;i<=n;i++)
{
fin >> a[i].val;
a[i].poz=i;
}
sort(a+1,a+n+1,cmp);
x=1;
for(i=1;i<=n;i++)
{
if(a[i].poz!=a[i-1].poz)
{
v[a[i].poz]=x;
x++;
}
else
v[a[i].poz]=x;
}
for (i=1;i<=n;i++)
{
start=v[i]+1;
finish=n;
query(1,1,n);
pos=v[i];
update(1,1,n);
}
fout << answ;
return 0;
}