#include <bits/stdc++.h>
using namespace std;

struct iofast_t {
    iofast_t() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr);
    }
} iofast;

struct uns_t {} uns;
template <typename Element, typename Head, typename ...Args>
auto vec(Element init, Head arg, Args ...args) {
    if constexpr (sizeof...(Args) == 0) return std::vector(arg, init);
    else return std::vector(arg, vec(init, args...));
}
template <typename Element, typename Head, typename ...Args>
auto vec(uns_t, Head arg, Args ...args) {
    return vec(Element(), arg, args...);
}

template <typename T, typename Compare = less<T>>
T &chmin(T &l, T r, Compare &&f = less<T>()) { return l = min(l, r, f); }
template <typename T, typename Compare = less<T>>
T &chmax(T &l, T r, Compare &&f = less<T>()) { return l = max(l, r, f); }

int main() {
    int64_t n; cin >> n;

    auto r = vec<int64_t>(uns, 0);

    int p = -1;
    for (int i = 0; i < n; ++i) {
        int a; cin >> a;

        if (p != a && a == 1) {
            r.push_back(0);
        }
        if (a == 1) {
            ++r.back();
        }

        p = a;
    }

    auto ans = n * (n + 1) / 2;
    for (auto v : r) {
        ans -= v * (v + 1) / 2;
    }

    cout << ans << endl;
}