#include
#include
#include
#include
#include
//#include
using namespace std;
typedef long long ll;
const int maxn = 1e6 + 10;
int segment_tree[maxn];
void build(int node, int L, int R) {
if(L == R) {
segment_tree[node] = 0;
}
else {
int mid = (L + R) / 2;
build(2 * node, L, mid);
build(2 * node + 1, mid + 1, R);
segment_tree[node] = segment_tree[2 * node] + segment_tree[2 * node + 1];
}
}
int query(int node, int L, int R, int i, int j) {
// L R i L R j L R
if(i <= L and R <= j) {
return segment_tree[node];
}
if(R < i or j < L) {
return 0;
}
int mid = (L + R) / 2;
return query(2 * node, L, mid, i, j) + query(2 * node + 1, mid + 1, R, i, j);
}
void update(int node, int L, int R, int idx) {
if(L == R) {
segment_tree[node] += 1;
return;
}
int mid = (L + R) / 2;
if(idx <= mid) {
update(2 * node, L, mid, idx);
}
else {
update(2 * node + 1, mid + 1, R, idx);
}
segment_tree[node] = segment_tree[2 * node] + segment_tree[2 * node + 1];
}
int main() {
ios_base::sync_with_stdio(false);
int n;
cin >> n;
vector v(n);
vector > compressed;
for(int i = 0; i < n; i++) {
cin >> v[i];
compressed.push_back(make_pair(v[i], i));
}
sort(compressed.begin(), compressed.end());
vector tmp;
for(int i = 0; i < n; i++) {
tmp.push_back(compressed[i].second);
}
reverse(tmp.begin(), tmp.end());
build(1, 0, n);
vector smaller;
for(int i = 0; i < n; i++) {
update(1, 0, n, tmp[i]);
smaller.push_back(query(1, 0, n, 0, tmp[i] - 1));
}
build(1, 0, n);
vector bigger;
for(int i = n - 1; i >= 0; i--) {
update(1, 0, n, tmp[i]);
bigger.push_back(query(1, 0, n, tmp[i] + 1, n));
}
reverse(bigger.begin(), bigger.end());
ll res = 0;
for(int i = 0; i < n; i++) {
res += bigger[i] * smaller[i];
}
cout << res << endl;
return 0;
}