#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
using ll = long long;

struct BIT {
    BIT(int n) : b(n + 1), n(n) {}
    void add(int i, int v) {
        for (int k = i + 1; k <= n; k += k & -k) b[k] += v;
    }
    int sum(int k) {
        int s = 0;
        for (; k > 0; k -= k & -k) s += b[k];
        return s;
    }
    vector<int> b;
    int n;
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin >> n;

    BIT bt(n);
    ll r = 0;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        a--;

        r += bt.sum(a);
        bt.add(a, 1);
    }

    cout << n * (n - 1) / 2 - r << endl;

    return 0;
}