#define CPP17
#include <limits>
#include <initializer_list>
#include <utility>
#include <bitset>
#include <tuple>
#include <type_traits>
#include <functional>
#include <string>
#include <array>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <iterator>
#include <algorithm>
#include <complex>
#include <random>
#include <numeric>
#include <iostream>
#include <iomanip>
#include <sstream>
#include <regex>
#include <cassert>
#include <cstddef>
#ifdef CPP17
#include <variant>
#endif

#define endl codeforces

#define ALL(v) std::begin(v), std::end(v)
#define ALLR(v) std::rbegin(v), std::rend(v)

using ll = std::int64_t;
using ull = std::uint64_t;
using pii = std::pair<int, int>;
using tii = std::tuple<int, int, int>;
using pll = std::pair<ll, ll>;
using tll = std::tuple<ll, ll, ll>;
using size_type = ssize_t;
template <typename T> using vec = std::vector<T>;
template <typename T> using vvec = vec<vec<T>>;

template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }

template <typename T, std::size_t Head, std::size_t... Tail> 
struct multi_dim_array { using type = std::array<typename multi_dim_array<T, Tail...>::type, Head>; };

template <typename T, std::size_t Head> 
struct multi_dim_array<T, Head> { using type = std::array<T, Head>; };

template <typename T, std::size_t... Args> using mdarray = typename multi_dim_array<T, Args...>::type;

#ifdef CPP17
template <typename T, typename F, typename... Args> 
void fill_seq(T &t, F f, Args... args) { 
    if constexpr (std::is_invocable<F, Args...>::value) { 
        t = f(args...); 
    } else { 
        for (size_type i = 0; i < t.size(); i++) fill_seq(t[i], f, args..., i); 
    } 
}
#endif

template <typename T> vec<T> make_v(size_type sz) { return vec<T>(sz); }

template <typename T, typename... Tail> 
auto make_v(size_type hs, Tail&&... ts) { 
    auto v = std::move(make_v<T>(std::forward<Tail>(ts)...)); 
    return vec<decltype(v)>(hs, v); 
}

namespace init__ { 
struct InitIO { 
    InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } 
} init_io; 
}
#define CPP17


namespace utility {

template <typename T>
using validate_integer = typename std::enable_if<std::is_integral<T>::value, ll>::type;

template <typename T>
auto popcount(T n) -> validate_integer<T> {
    return __builtin_popcountll(n);
}

// 0 indexed
template <typename T>
auto msb(T n) -> validate_integer<T> {
    return 64 - __builtin_clzll(n) - 1;
}

template <typename T>
constexpr auto ceil_pow2(T s) -> validate_integer<T> {
    ll ret = 1;
    while (ret < s) ret *= 2;
    return ret;
}

}

namespace tree {

template <typename T>
struct BIT {
    using size_type = ssize_t;
    vec<T> data;
    T id_ele;

    BIT(size_type sz, T id_ele) : id_ele(id_ele) {
        data = vec<T>(utility::ceil_pow2(sz) + 1, id_ele);
    }

    // [0, pos)
    T sum(size_type pos) const {
        T ret = id_ele;
        for (; 0 < pos; pos -= pos & -pos) ret += data[pos];
        return ret;
    }

    // [l, r)
    T sum(size_type l, size_type r) const { 
        return sum(r) - sum(l); 
    }

    void add(ll pos, T delta) {
        for (++pos; pos < data.size(); pos += pos & -pos) data[pos] += delta;
    }

    // sum(ret) < bound <= sum(ret+1)
    size_type lower_bound(T bound) const {
        if (data.back() < bound) return data.size();
        T sum = id_ele;
        size_type ret = 0;
        for (size_type i = (data.size() - 1) / 2; 0 < i; i /= 2) {
            if (sum + data[ret + i] < bound) {
                ret += i;
                sum += data[ret];
            }
        }
        return ret;
    }
};

}

ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }

pll cnt_div(ll n) {
    ll cnt2 = 0, cnt5 = 0;
    while (n % 2 == 0) {
        cnt2++;
        n /= 2;
    }
    while (n % 5 == 0) {
        cnt5++;
        n /= 5;
    }

    return pll(cnt2, cnt5);
}

int main() {
    const size_type SIZE = 64;
    const size_type SIZE2 = SIZE * 2 + 1;
    vec<tree::BIT<ll>> bitv(SIZE2, tree::BIT<ll>(SIZE2, 0));

    ll n;
    std::cin >> n;
    vec<std::string> vs(n);
    for (auto &&e : vs) std::cin >> e;

    ll ans = 0;

    for (auto &&s : vs) {
        ll num = 0, den = 1;
        {
            for (char c : s) {
                if (c == '.') continue;
                num = num * 10 + (c - '0');
            }
            auto ite = std::find(ALL(s), '.');
            ll idx = std::distance(s.begin(), ite);
            ll sz = s.size();
            for (ll i = idx + 1; i < sz; i++) den *= 10;
        }

        ll g = gcd(num, den);
        num /= g;
        den /= g;
        auto [ n2, n5 ] = [&] {
            auto [ a, b ] = cnt_div(num);
            auto [ c, d ] = cnt_div(den);
            return pll(a - c, b - d);
        }();


        ans += bitv[SIZE - n2].sum(SIZE - n5, SIZE2);

        for (ll i = 0; i <= n2 + SIZE; i++) bitv[i].add(n5 + SIZE, 1);
    }

    std::cout << ans << "\n";
    return 0;
}


Measured memory_bytes: 9592