include[HTML_REMOVED]
const int N =1000010;
using namespace std;
int q[N],tmp[N];
long long sort(int q[],int l ,int r){
if(l>=r)return 0;
int mid = l + (r - l >> 1);int i=l,j=mid+1,k=0;long long re=0;
re+=sort(q,l,mid),re+=sort(q,mid+1,r);
while(i<=mid&&j<=r){
if(q[i]<=q[j]){
tmp[k]=q[i];
}
else{
tmp[k]=q[j];
re+=mid-i+1;
}
}
while(i<=mid){
tmp[k]=q[i];
}
while(j<=r)
{
tmp[k]=q[j];
}
for(int i=l,k=0;i<=r;i,k){
q[i]=tmp[k];
}
return re;
}
int main(){
int n;
cin >> n;
for(int i = 0; i < n;i++){
cin >> q[i];
}
cout << sort(q, 0 ,n - 1);
}