#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long ll;
// The Fenwick Tree (BIT) Structure
struct FenwickTree {
int n;
vector<int> tree;
FenwickTree(int n) : n(n), tree(n + 1, 0) {}
// Adds 1 to the frequency of a certain height
void update(int i, int delta) {
for (; i <= n; i += i & -i) {
tree[i] += delta;
}
}
// Queries how many mountains have been seen up to height i
int query(int i) {
int sum = 0;
for (; i > 0; i -= i & -i) {
sum += tree[i];
}
return sum;
}
};
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int n;
if (!(cin >> n)) return 0;
vector<int> a(n);
vector<int> coords;
for (int i = 0; i < n; i++) {
cin >> a[i];
coords.push_back(a[i]);
}
// --- Coordinate Compression ---
// This turns heights like [100, 999, 50] into [2, 3, 1]
sort(coords.begin(), coords.end());
coords.erase(unique(coords.begin(), coords.end()), coords.end());
for (int i = 0; i < n; i++) {
a[i] = lower_bound(coords.begin(), coords.end(), a[i]) - coords.begin() + 1;
}
int maxHeight = coords.size();
vector<int> left_count(n), right_count(n);
// --- Step 1: Count smaller elements to the left ---
FenwickTree ft_left(maxHeight);
for (int i = 0; i < n; i++) {
left_count[i] = ft_left.query(a[i] - 1);
ft_left.update(a[i], 1);
}
// --- Step 2: Count smaller elements to the right ---
FenwickTree ft_right(maxHeight);
for (int i = n - 1; i >= 0; i--) {
right_count[i] = ft_right.query(a[i] - 1);
ft_right.update(a[i], 1);
}
// --- Step 3: Calculate total combinations ---
ll total = 0;
for (int i = 0; i < n; i++) {
total += (ll)left_count[i] * right_count[i];
}
cout << total << endl;
return 0;
}
