#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
#define ll long long
typedef __gnu_pbds::tree<ll, __gnu_pbds::null_type, less<ll>,
__gnu_pbds::rb_tree_tag, __gnu_pbds::tree_order_statistics_node_update> ordered_set;
#define ll long long
#define F first
#define S second
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n;
cin>>n;
vector<ll> a(n), b(n);
ordered_set os;
for(int i=0;i<n;++i) {
cin>>a[i];
b[i] = os.order_of_key(a[i]);
os.insert(a[i]);
}
os.clear();
ll ans = 0;
for(int i=n-1;i>=0;--i) {
ans += (b[i] * os.order_of_key(a[i]));
os.insert(a[i]);
}
cout<<ans<<'\n';
return 0;
}
