#include <bits/stdc++.h>

#define rep(i,s,n) for(int i = int(s); i < int(n); i++)

#define all(v) (v).begin(), (v).end()

using i64 = std::int64_t;

template <class T> void arg_sort_ll(std::vector<std::pair<T, T>> &a) {
    using Point = std::pair<T, T>;
    int n = a.size();
    std::vector ps(4, std::vector<Point>());
    auto idx = [](Point v) -> int {
        if (v.second >= 0)
            return (v.first >= 0) ? 0 : 1;
        else
            return (v.first >= 0) ? 3 : 2;
    };
    for (auto p : a) {
        assert(!(p.first == 0 && p.second == 0));
        ps[idx(p)].emplace_back(p);
    }
    a.clear();
    a.reserve(n);
    for (int j = 0; j < 4; j++) {
        int i = (3 + j) % 4;
        std::sort(ps[i].begin(), ps[i].end(), [](Point &p1, Point &p2) -> bool {
            T flag = p1.first * p2.second - p2.first * p1.second;
            return flag == 0 ? (p1.first * p1.first + p1.second * p1.second <
                                p2.first * p2.first + p2.second * p2.second)
                             : flag > 0;
        });
        for (auto &p : ps[i]) a.emplace_back(p);
    }
    return;
}

template<class T>
bool chmin(T &a, T b) {
    if(a < b) return false;
    a = b;
    return true;
}

int main() {
    std::cout << std::fixed << std::setprecision(15);
    int n;
    i64 h;
    std::cin >> n >> h;
    std::vector<std::pair<i64,i64>> ps(n);
    std::vector<i64> xs;
    for(auto &[x, y]: ps) {
        std::cin >> x >> y;
        xs.emplace_back(x);
    }
    std::sort(all(xs));
    xs.erase(std::unique(all(xs)), xs.end());
    std::vector<int> arg_ord;
    {
        std::vector<std::pair<i64,i64>> ret;
        std::map<std::pair<i64, i64>, int> map;
        rep(i,0,n) {
            auto [x, y] = ps[i];
            ret.emplace_back(2 * x, 2 * y - h);
            map[{2 * x, 2 * y - h}] = i;
        }
        arg_sort_ll(ret);
        for(auto [x, y]: ret) {
            arg_ord.emplace_back(map[{x, y}]);
        }
    }
    using ld = long double;
    ld ans = std::numeric_limits<ld>::max();
    auto calc_score = [](const std::vector<i64> &a) -> ld {
        if(a[2] == 0) return 0;
        return ld(a[0]) - ld(a[1] * a[1]) / ld(4 * a[2]);
    };
    for(auto tx: xs) {
        std::vector<i64> u(3, 0), d(3, 0);
        for(auto [x, y]: ps) {
            if(x < tx) {
                u[0] += (y - h) * (y - h);
                u[1] += -2 * (y - h) * x;
                u[2] += x * x;
            }
            else {
                d[0] += y * y;
                d[1] += -2 * x * y;
                d[2] += x * x;
            }
        }
        chmin(ans, calc_score(u) + calc_score(d));
        for(auto i: arg_ord) {
            auto [x, y] = ps[i];
            if(x < tx) {
                u[0] -= (y - h) * (y - h);
                u[1] -= -2 * (y - h) * x;
                u[2] -= x * x;

                d[0] += y * y;
                d[1] += -2 * x * y;
                d[2] += x * x;
            }
            else {
                d[0] -= y * y;
                d[1] -= -2 * x * y;
                d[2] -= x * x;

                u[0] += (y - h) * (y - h);
                u[1] += -2 * (y - h) * x;
                u[2] += x * x;
            }
            chmin(ans, calc_score(u) + calc_score(d));
        }
    }
    std::cout << ans << '\n';
}