// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")
// #define INTERACTIVE

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

namespace templates {
// type
using ll  = long long;
using ull = unsigned long long;
using Pii = pair<int, int>;
using Pil = pair<int, ll>;
using Pli = pair<ll, int>;
using Pll = pair<ll, ll>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using qp = priority_queue<T, vector<T>, greater<T>>;
// clang-format off
#define vec(T, A, ...) vector<T> A(__VA_ARGS__);
#define vvec(T, A, h, ...) vector<vector<T>> A(h, vector<T>(__VA_ARGS__));
#define vvvec(T, A, h1, h2, ...) vector<vector<vector<T>>> A(h1, vector<vector<T>>(h2, vector<T>(__VA_ARGS__)));
// clang-format on

// for loop
#define fori1(a) for (ll _ = 0; _ < (a); _++)
#define fori2(i, a) for (ll i = 0; i < (a); i++)
#define fori3(i, a, b) for (ll i = (a); i < (b); i++)
#define fori4(i, a, b, c) for (ll i = (a); ((c) > 0 || i > (b)) && ((c) < 0 || i < (b)); i += (c))
#define overload4(a, b, c, d, e, ...) e
#define fori(...) overload4(__VA_ARGS__, fori4, fori3, fori2, fori1)(__VA_ARGS__)

// declare and input
// clang-format off
#define INT(...) int __VA_ARGS__; inp(__VA_ARGS__);
#define LL(...) ll __VA_ARGS__; inp(__VA_ARGS__);
#define STRING(...) string __VA_ARGS__; inp(__VA_ARGS__);
#define CHAR(...) char __VA_ARGS__; inp(__VA_ARGS__);
#define DOUBLE(...) double __VA_ARGS__; STRING(str___); __VA_ARGS__ = stod(str___);
#define VEC(T, A, n) vector<T> A(n); inp(A);
#define VVEC(T, A, n, m) vector<vector<T>> A(n, vector<T>(m)); inp(A);
// clang-format on

// const value
const ll MOD1   = 1000000007;
const ll MOD9   = 998244353;
const double PI = acos(-1);

// other macro
#if !defined(RIN__LOCAL) && !defined(INTERACTIVE)
#define endl "\n"
#endif
#define spa ' '
#define len(A) ll(A.size())
#define all(A) begin(A), end(A)

// function
vector<char> stoc(string &S) {
    int n = S.size();
    vector<char> ret(n);
    for (int i = 0; i < n; i++) ret[i] = S[i];
    return ret;
}
string ctos(vector<char> &S) {
    int n      = S.size();
    string ret = "";
    for (int i = 0; i < n; i++) ret += S[i];
    return ret;
}

template <class T>
auto min(const T &a) {
    return *min_element(all(a));
}
template <class T>
auto max(const T &a) {
    return *max_element(all(a));
}
template <class T, class S>
auto clamp(T &a, const S &l, const S &r) {
    return (a > r ? r : a < l ? l : a);
}
template <class T, class S>
inline bool chmax(T &a, const S &b) {
    return (a < b ? a = b, 1 : 0);
}
template <class T, class S>
inline bool chmin(T &a, const S &b) {
    return (a > b ? a = b, 1 : 0);
}
template <class T, class S>
inline bool chclamp(T &a, const S &l, const S &r) {
    auto b = clamp(a, l, r);
    return (a != b ? a = b, 1 : 0);
}

template <typename T>
T sum(vector<T> &A) {
    T tot = 0;
    for (auto a : A) tot += a;
    return tot;
}

template <typename T>
vector<T> compression(vector<T> X) {
    sort(all(X));
    X.erase(unique(all(X)), X.end());
    return X;
}

// input and output
namespace io {
// __int128_t
std::ostream &operator<<(std::ostream &dest, __int128_t value) {
    std::ostream::sentry s(dest);
    if (s) {
        __uint128_t tmp = value < 0 ? -value : value;
        char buffer[128];
        char *d = std::end(buffer);
        do {
            --d;
            *d = "0123456789"[tmp % 10];
            tmp /= 10;
        } while (tmp != 0);
        if (value < 0) {
            --d;
            *d = '-';
        }
        int len = std::end(buffer) - d;
        if (dest.rdbuf()->sputn(d, len) != len) {
            dest.setstate(std::ios_base::badbit);
        }
    }
    return dest;
}

// vector<T>
template <typename T>
istream &operator>>(istream &is, vector<T> &A) {
    for (auto &a : A) is >> a;
    return is;
}
template <typename T>
ostream &operator<<(ostream &os, vector<T> &A) {
    for (size_t i = 0; i < A.size(); i++) {
        os << A[i];
        if (i != A.size() - 1) os << ' ';
    }
    return os;
}

// vector<vector<T>>
template <typename T>
istream &operator>>(istream &is, vector<vector<T>> &A) {
    for (auto &a : A) is >> a;
    return is;
}
template <typename T>
ostream &operator<<(ostream &os, vector<vector<T>> &A) {
    for (size_t i = 0; i < A.size(); i++) {
        os << A[i];
        if (i != A.size() - 1) os << endl;
    }
    return os;
}

// pair<S, T>
template <typename S, typename T>
istream &operator>>(istream &is, pair<S, T> &A) {
    is >> A.first >> A.second;
    return is;
}
template <typename S, typename T>
ostream &operator<<(ostream &os, pair<S, T> &A) {
    os << A.first << ' ' << A.second;
    return os;
}

// vector<pair<S, T>>
template <typename S, typename T>
istream &operator>>(istream &is, vector<pair<S, T>> &A) {
    for (size_t i = 0; i < A.size(); i++) {
        is >> A[i];
    }
    return is;
}
template <typename S, typename T>
ostream &operator<<(ostream &os, vector<pair<S, T>> &A) {
    for (size_t i = 0; i < A.size(); i++) {
        os << A[i];
        if (i != A.size() - 1) os << endl;
    }
    return os;
}

// tuple
template <typename T, size_t N>
struct TuplePrint {
    static ostream &print(ostream &os, const T &t) {
        TuplePrint<T, N - 1>::print(os, t);
        os << ' ' << get<N - 1>(t);
        return os;
    }
};
template <typename T>
struct TuplePrint<T, 1> {
    static ostream &print(ostream &os, const T &t) {
        os << get<0>(t);
        return os;
    }
};
template <typename... Args>
ostream &operator<<(ostream &os, const tuple<Args...> &t) {
    TuplePrint<decltype(t), sizeof...(Args)>::print(os, t);
    return os;
}

// io functions
void FLUSH() {
    cout << flush;
}

void print() {
    cout << endl;
}
template <class Head, class... Tail>
void print(Head &&head, Tail &&...tail) {
    cout << head;
    if (sizeof...(Tail)) cout << spa;
    print(std::forward<Tail>(tail)...);
}

template <typename T, typename S>
void prisep(vector<T> &A, S sep) {
    int n = A.size();
    for (int i = 0; i < n; i++) {
        cout << A[i];
        if (i != n - 1) cout << sep;
    }
    cout << endl;
}
template <typename T, typename S>
void priend(T A, S end) {
    cout << A << end;
}
template <typename T>
void prispa(T A) {
    priend(A, spa);
}
template <typename T, typename S>
bool printif(bool f, T A, S B) {
    if (f)
        print(A);
    else
        print(B);
    return f;
}

template <class... T>
void inp(T &...a) {
    (cin >> ... >> a);
}

} // namespace io
using namespace io;

// read graph
vector<vector<int>> read_edges(int n, int m, bool direct = false, int indexed = 1) {
    vector<vector<int>> edges(n, vector<int>());
    for (int i = 0; i < m; i++) {
        INT(u, v);
        u -= indexed;
        v -= indexed;
        edges[u].push_back(v);
        if (!direct) edges[v].push_back(u);
    }
    return edges;
}
vector<vector<int>> read_tree(int n, int indexed = 1) {
    return read_edges(n, n - 1, false, indexed);
}

template <typename T = long long>
vector<vector<pair<int, T>>> read_wedges(int n, int m, bool direct = false, int indexed = 1) {
    vector<vector<pair<int, T>>> edges(n, vector<pair<int, T>>());
    for (int i = 0; i < m; i++) {
        INT(u, v);
        T w;
        inp(w);
        u -= indexed;
        v -= indexed;
        edges[u].push_back({v, w});
        if (!direct) edges[v].push_back({u, w});
    }
    return edges;
}
template <typename T = long long>
vector<vector<pair<int, T>>> read_wtree(int n, int indexed = 1) {
    return read_wedges<T>(n, n - 1, false, indexed);
}

// yes / no
namespace yesno {

// yes
inline bool yes(bool f = true) {
    cout << (f ? "yes" : "no") << endl;
    return f;
}
inline bool Yes(bool f = true) {
    cout << (f ? "Yes" : "No") << endl;
    return f;
}
inline bool YES(bool f = true) {
    cout << (f ? "YES" : "NO") << endl;
    return f;
}

// no
inline bool no(bool f = true) {
    cout << (!f ? "yes" : "no") << endl;
    return f;
}
inline bool No(bool f = true) {
    cout << (!f ? "Yes" : "No") << endl;
    return f;
}
inline bool NO(bool f = true) {
    cout << (!f ? "YES" : "NO") << endl;
    return f;
}

// possible
inline bool possible(bool f = true) {
    cout << (f ? "possible" : "impossible") << endl;
    return f;
}
inline bool Possible(bool f = true) {
    cout << (f ? "Possible" : "Impossible") << endl;
    return f;
}
inline bool POSSIBLE(bool f = true) {
    cout << (f ? "POSSIBLE" : "IMPOSSIBLE") << endl;
    return f;
}

// impossible
inline bool impossible(bool f = true) {
    cout << (!f ? "possible" : "impossible") << endl;
    return f;
}
inline bool Impossible(bool f = true) {
    cout << (!f ? "Possible" : "Impossible") << endl;
    return f;
}
inline bool IMPOSSIBLE(bool f = true) {
    cout << (!f ? "POSSIBLE" : "IMPOSSIBLE") << endl;
    return f;
}

// Alice Bob
inline bool Alice(bool f = true) {
    cout << (f ? "Alice" : "Bob") << endl;
    return f;
}
inline bool Bob(bool f = true) {
    cout << (f ? "Bob" : "Alice") << endl;
    return f;
}

// Takahashi Aoki
inline bool Takahashi(bool f = true) {
    cout << (f ? "Takahashi" : "Aoki") << endl;
    return f;
}
inline bool Aoki(bool f = true) {
    cout << (f ? "Aoki" : "Takahashi") << endl;
    return f;
}

} // namespace yesno
using namespace yesno;

} // namespace templates
using namespace templates;

template <typename T = long long>
struct Point {
    T x;
    T y;
    Point() {}
    Point(T x, T y) : x(x), y(y) {}

    int area() {
        if (y < 0) {
            if (x < 0)
                return 1;
            else
                return 2;
        } else {
            if (x >= 0)
                return 3;
            else
                return 4;
        }
    }

    bool operator<(Point &rhs) {
        int ap = area();
        int aq = rhs.area();
        if (x == rhs.x && y == rhs.y) {
            return false;
        }
        if (ap == aq) {
            if (x == 0 && y == 0) return true;
            return x * rhs.y > rhs.x * y;
        } else {
            return ap < aq;
        }
    }

    bool operator==(Point &rhs) {
        return x == rhs.x && y == rhs.y;
    }

    friend std::ostream &operator<<(std::ostream &os, Point &p) {
        os << p.x << " " << p.y;
        return os;
    }

    friend std::istream &operator>>(std::istream &is, Point &p) {
        is >> p.x >> p.y;
        return is;
    }
};

template <typename T>
T cross3(Point<T> &a, Point<T> &b, Point<T> &c) {
    return (b.x - a.x) * (c.y - a.y) - (b.y - a.y) * (c.x - a.x);
}

template <typename T = long long>
std::vector<Point<T>> convexHull(std::vector<Point<T>> P, bool multi = true) {
    sort(P.begin(), P.end(), [](Point<T> &l, Point<T> &r) {
        if (l.x == r.x) return l.y < r.y;
        return l.x < r.x;
    });
    // 同一座標は 1 つにまとめる
    P.erase(unique(P.begin(), P.end()), P.end());
    if (P.size() <= 1) return P;
    std::vector<Point<T>> Q;
    int n = P.size();
    if (multi) {
        for (auto p : P) {
            while (Q.size() > 1u && cross3(Q[Q.size() - 1u], Q[Q.size() - 2u], p) > 0) {
                Q.pop_back();
            }
            Q.push_back(p);
        }
        size_t t = Q.size();
        for (int i = n - 2; i >= 0; i--) {
            Point<T> p = P[i];
            while (Q.size() > t && cross3(Q[Q.size() - 1u], Q[Q.size() - 2u], p) > 0) {
                Q.pop_back();
            }
            Q.push_back(p);
        }
    } else {
        for (auto p : P) {
            while (Q.size() > 1u && cross3(Q[Q.size() - 1u], Q[Q.size() - 2u], p) >= 0) {
                Q.pop_back();
            }
            Q.push_back(p);
        }
        size_t t = Q.size();
        for (int i = n - 2; i >= 0; i--) {
            Point<T> p = P[i];
            while (Q.size() > t && cross3(Q[Q.size() - 1u], Q[Q.size() - 2u], p) >= 0) {
                Q.pop_back();
            }
            Q.push_back(p);
        }
    }
    Q.pop_back();
    return Q;
}

using ld = long double;
void solve() {
    ll n;
    ll x0, y0;
    ld d;
    ld t;
    inp(n, x0, y0, d, t);

    using Po = Point<ll>;
    VEC(Po, points, n);

    auto P = points;
    P.push_back(Po(0, 0));
    auto Q = convexHull(P);

    int lp, rp;
    fori(i, len(Q)) {
        if (Q[i].x == 0 and Q[i].y == 0) {
            lp = i == 0 ? len(Q) - 1 : i - 1;
            rp = i == len(Q) - 1 ? 0 : i + 1;
        }
    }

    ld arg = atan2(y0, x0);

    ld arg_l;
    {
        ld x  = Q[lp].x;
        ld y  = Q[lp].y;
        ld l_ = atan2(y, x);
        ld r_ = l_ + PI / 2.0;
        fori(100) {
            ld mid  = (l_ + r_) / 2.0;
            ld dx   = cos(mid);
            ld dy   = sin(mid);
            ld dist = abs(dy * x - dx * y) / sqrt(dx * dx + dy * dy);
            if (dist >= d) {
                r_ = mid;
            } else {
                l_ = mid;
            }
        }

        arg_l = l_;
    }

    ld arg_r;
    {
        ld x  = Q[rp].x;
        ld y  = Q[rp].y;
        ld l_ = atan2(y, x);
        ld r_ = l_ - PI / 2.0;
        fori(100) {
            ld mid  = (l_ + r_) / 2.0;
            ld dx   = cos(mid);
            ld dy   = sin(mid);
            ld dist = abs(dy * x - dx * y) / sqrt(dx * dx + dy * dy);
            if (dist >= d) {
                r_ = mid;
            } else {
                l_ = mid;
            }
        }

        arg_r = l_;
    }

    arg_l -= arg;
    arg_r -= arg;
    while (arg_l < 0) arg_l += 2 * PI;
    while (arg_r < 0) arg_r += 2 * PI;
    while (arg_l >= 2 * PI) arg_l -= 2 * PI;
    while (arg_r >= 2 * PI) arg_r -= 2 * PI;

    ld loop = arg_l - arg_r;
    if (loop < 0) loop += 2 * PI;

    ll loop_cnt = int(t / (2 * PI));
    ld ans      = loop * loop_cnt;
    t -= loop_cnt * 2 * PI;

    if (arg_r <= arg_l) {
        ans += min<ld>(arg_l, t) - min<ld>(arg_r, t);
    } else {
        ans += min<ld>(arg_l, t);
        ans += max<ld>(0, t - arg_r);
    }
    print(ans);
}

int main() {
#ifndef INTERACTIVE
    std::cin.tie(0)->sync_with_stdio(0);
#endif
    std::cout << std::fixed << std::setprecision(12);
    int t;
    t = 1;
    // std::cin >> t;
    while (t--) solve();
    return 0;
}

// // #pragma GCC target("avx2")
// // #pragma GCC optimize("O3")
// // #pragma GCC optimize("unroll-loops")
// // #define INTERACTIVE
//
// #include "kyopro-cpp/template.hpp"
//
// #include "geometry/convexHull.hpp"
//
// using ld = long double;
// void solve() {
//     ll n;
//     ll x0, y0;
//     ld d;
//     ld t;
//     inp(n, x0, y0, d, t);
//
//     using Po = Point<ll>;
//     VEC(Po, points, n);
//
//     auto P = points;
//     P.push_back(Po(0, 0));
//     auto Q = convexHull(P);
//
//     int lp, rp;
//     fori(i, len(Q)) {
//         if (Q[i].x == 0 and Q[i].y == 0) {
//             lp = i == 0 ? len(Q) - 1 : i - 1;
//             rp = i == len(Q) - 1 ? 0 : i + 1;
//         }
//     }
//
//     ld arg = atan2(y0, x0);
//
//     ld arg_l;
//     {
//         ld x  = Q[lp].x;
//         ld y  = Q[lp].y;
//         ld l_ = atan2(y, x);
//         ld r_ = l_ + PI / 2.0;
//         fori(100) {
//             ld mid  = (l_ + r_) / 2.0;
//             ld dx   = cos(mid);
//             ld dy   = sin(mid);
//             ld dist = abs(dy * x - dx * y) / sqrt(dx * dx + dy * dy);
//             if (dist >= d) {
//                 r_ = mid;
//             } else {
//                 l_ = mid;
//             }
//         }
//
//         arg_l = l_;
//     }
//
//     ld arg_r;
//     {
//         ld x  = Q[rp].x;
//         ld y  = Q[rp].y;
//         ld l_ = atan2(y, x);
//         ld r_ = l_ - PI / 2.0;
//         fori(100) {
//             ld mid  = (l_ + r_) / 2.0;
//             ld dx   = cos(mid);
//             ld dy   = sin(mid);
//             ld dist = abs(dy * x - dx * y) / sqrt(dx * dx + dy * dy);
//             if (dist >= d) {
//                 r_ = mid;
//             } else {
//                 l_ = mid;
//             }
//         }
//
//         arg_r = l_;
//     }
//
//     arg_l -= arg;
//     arg_r -= arg;
//     while (arg_l < 0) arg_l += 2 * PI;
//     while (arg_r < 0) arg_r += 2 * PI;
//     while (arg_l >= 2 * PI) arg_l -= 2 * PI;
//     while (arg_r >= 2 * PI) arg_r -= 2 * PI;
//
//     ld loop = arg_l - arg_r;
//     if (loop < 0) loop += 2 * PI;
//
//     ll loop_cnt = int(t / (2 * PI));
//     ld ans      = loop * loop_cnt;
//     t -= loop_cnt * 2 * PI;
//
//     if (arg_r <= arg_l) {
//         ans += min<ld>(arg_l, t) - min<ld>(arg_r, t);
//     } else {
//         ans += min<ld>(arg_l, t);
//         ans += max<ld>(0, t - arg_r);
//     }
//     print(ans);
// }
//
// int main() {
// #ifndef INTERACTIVE
//     std::cin.tie(0)->sync_with_stdio(0);
// #endif
//     std::cout << std::fixed << std::setprecision(12);
//     int t;
//     t = 1;
//     // std::cin >> t;
//     while (t--) solve();
//     return 0;
// }