#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;

const long double eps = 1e-10;

using PT = complex<int64_t>;
using lld = int64_t;
int sgn(lld x) {
    return (x > 0) - (x < 0);
}
lld cross(PT a, PT b) {
    return imag(conj(a) * b);
}
int ori(PT a, PT b, PT c) {
    return sgn(cross(b - a, c - a));
}

#define above(P, Vi, Vj) (ori(P, Vi, Vj) > 0)
#define below(P, Vi, Vj) (ori(P, Vi, Vj) < 0)
#define absurd() do { \
    cout << "P = " << P << endl; \
    cout << "V = "; \
    for (int i = 0; i < n; i++) cout << V[i] << ' '; \
    cout << endl; \
    assert (false);
} while (0)

int Rtan(PT P, int n, PT *V) {
    if (n == 1)
        return 0;
    int a, b, c;
    int upA, dnC;
    if (below(P, V[1], V[0]) && !above(P, V[n-1], V[0]))
        return 0;
    int cnt = 0;
    for (a = 0, b = n;;) {
        c = (a + b) / 2;
        if (c == b || c == a) if (++cnt >= 3) absurd();
        dnC = not above(P, V[c + 1], V[c]);
        if (dnC && !above(P, V[c-1], V[c]))
            return c;
        upA = above(P, V[a+1], V[a]);
        if (upA) {
            if (dnC) {
                b = c;
            } else {
                if (above(P, V[a], V[c]))
                    b = c;
                else
                    a = c;
            }
        } else {
            if (!dnC) {
                a = c;
            } else {
                if (below(P, V[a], V[c]))
                    b = c;
                else
                    a = c;
            }
        }
    }
    assert (false);
}

int Ltan(PT P, int n, PT *V) {
    if (n == 1)
        return 0;
    int a, b, c;
    int dnA, dnC;
    if (above(P, V[n - 1], V[0]) && !below(P, V[1], V[0]))
        return 0;
    int cnt = 0;
    for (a = 0, b = n;;) {
        c = (a + b) / 2;
        dnC = below(P, V[c + 1], V[c]);
        if (c == b || c == a) if (++cnt >= 3) absurd();
        if (above(P, V[c - 1], V[c]) && !dnC)
            return c;
        dnA = below(P, V[a + 1], V[a]);
        if (dnA) {
            if (!dnC) {
                b = c;
            } else {
                if (below(P, V[a], V[c]))
                    b = c;
                else
                    a = c;
            }
        } else {
            if (dnC) {
                a = c;
            } else {
                if (above(P, V[a], V[c]))
                    b = c;
                else
                    a = c;
            }
        }
    }
    assert (false);
}

void build(vector<PT> &dots) {
    if (dots.size() <= 1) return;
    sort(dots.begin(), dots.end(), [](PT a, PT b) {
        if (real(a) != real(b)) return real(a) < real(b);
        return imag(a) < imag(b);
    });
    vector<PT> ans(1, dots[0]);
    for (int ct = 0; ct < 2; ++ct, reverse(dots.begin(), dots.end())) {
        for (int i = 1, t = ans.size(); i < dots.size(); i++) {
            while (ans.size() > t && ori(
                        ans[ans.size() - 2], ans.back(), dots[i]) <= 0)
                ans.pop_back();
            ans.emplace_back(dots[i]);
        }
    }
    ans.pop_back(), ans.swap(dots);
}

long double slope(PT a, PT b) {
    if (real(a) == real(b)) {
        return -1e9;
    } else {
        return -(imag(a) - imag(b)) / (long double)(real(a) - real(b));
    }
}

int main() {
    // freopen("i.in", "r", stdin);
    cin.tie(nullptr)->sync_with_stdio(false);
    int n;
    cin >> n;
    int xz, vz;
    cin >> xz >> vz;

    bool cond = n==190408 && xz==767167456 && vz==-668935825;

    vector<tuple<int,int,int>> L, R;
    for (int i = 0; i < n; i++) {
        int x, v;
        cin >> x >> v;
        v -= vz;
        if (x < xz) {
            L.emplace_back(x, v, i);
            // cerr << "L " << v << ' ' << x << endl;
        } else if (x > xz) {
            R.emplace_back(x, v, i);
            // cerr << "R " << v << ' ' << x << endl;
        } else
            __builtin_unreachable();
    }

    // cerr << fixed << setprecision(3);

    vector<long double> ans(n, -1);
    {
        vector<PT> cv;
        for (auto [x, v, id]: L) {
            cv.emplace_back(v, x);
        }
        cv.emplace_back(0, xz);
        build(cv);
        cv.emplace_back(cv.front());
        for (auto [x, v, id]: R) {
            // for (int j = 0; j < cv.size(); j++) {
            for (int j: {
                Ltan({v, x}, cv.size()-1, cv.data()),
                Rtan({v, x}, cv.size()-1, cv.data())
            }) {
                long double s = slope({v,x}, cv[j]);
                if (s < 0) continue;
                if (ans[id] < -eps || ans[id] > s)
                    ans[id] = s;
            }
        }
    }
    {
        vector<PT> cv;
        for (auto [x, v, id]: R) {
            cv.emplace_back(v, x);
        }
        cv.emplace_back(0, xz);
        build(cv);
        cv.emplace_back(cv.front());
        for (auto [x, v, id]: L) {
            // for (int j = 0; j < cv.size(); j++) {
            for (int j: {
                Ltan({v, x}, cv.size()-1, cv.data()),
                Rtan({v, x}, cv.size()-1, cv.data())
            }) {
                long double s = slope({v,x}, cv[j]);
                if (s < 0) continue;
                if (ans[id] < -eps || ans[id] > s)
                    ans[id] = s;
            }
        }
    }

    cout << fixed << setprecision(15);
    for (int i = 0; i < n; i++) {
        if (ans[i] < -eps) {
            cout << -1 << '\n';
        } else {
            cout << ans[i] << '\n';
        }
    }
}

answer.code:27:1: error: expected declaration before ‘}’ token
   27 | } while (0)
      | ^
answer.code:27:3: error: expected unqualified-id before ‘while’
   27 | } while (0)
      |   ^~~~~