#include <bits/stdc++.h>
using namespace std;
using ldb = long double;
const ldb pi = acosl(-1);
const ldb eps = 1e-12;
struct point {
    ldb x, y;
    point operator+(const point& o) const { return {x + o.x, y + o.y}; }
    point operator-(const point& o) const { return {x - o.x, y - o.y}; }
    ldb operator*(const point& o) const { return x * o.x + y * o.y; };
    ldb operator^(const point& o) const { return x * o.y - y * o.x; };
    point operator*(const ldb o) const { return {x * o, y * o}; };
    point operator/(const ldb o) const { return {x / o, y / o}; };
    ldb th() const {
        ldb tmp = atan2l(y, x);

        // cout << x << " " << y << " " << tmp << '\n';
        return tmp < 0 ? tmp + 2 * pi : tmp;
    };
    ldb len() const { return sqrtl(x * x + y * y); }
    point rot(const ldb cosr, const ldb sinr) const { return {x * cosr - y * sinr, x * sinr + y * cosr}; }
};
// using pii = pair<>

struct circle {
    ldb r;
    pair<ldb, ldb> targent(const point& a) const {
        point e = a;
        e = e / e.len() * r;
        const ldb costh = r / a.len(), sinth = sqrt(1 - costh * costh);
        const point t1 = e.rot(costh, -sinth), t2 = e.rot(costh, sinth);
        return {(a - t1).th(), (a - t2).th()};
    }
};

int main() {
    int n, __x, __y, d;
    ldb t;
    ldb th;
    cin >> n >> __x >> __y >> d >> t;
    th = point{(ldb)__x, (ldb)__y}.th();
    vector<point> a(n);
    int vis[5];
    vis[1] = vis[4] = 0;
    for (int i = 0; i < n; ++i) {
        cin >> a[i].x >> a[i].y;
        vis[1] |= a[i].x > 0 && a[i].y > 0;
        vis[4] |= a[i].x > 0 && a[i].y < 0;
    }
    circle c(d);
    ldb mx = 0;
    ldb mn = 3 * pi;
    if (vis[1] && vis[4]) {
        th = th <= pi ? th + pi : th - pi;
        for (int i = 0; i < n; ++i) a[i] = a[i] * (-1);
    }
    for (int i = 0; i < n; ++i) {
        auto [t1, t2] = c.targent(a[i]);
        // cout << a[i].x << " " << a[i].y << " " << t1 << " " << t2 << '\n';
        mn = min(min(t1, mn), t2);
        mx = max(max(t1, t2), mx);
    }

    ldb ans = 0;
    int n1 = t / (2 * pi);
    t = t - n1 * (2 * pi);
    ans += n1 * (mx - mn);
    // cout << mx << " " << mn << '\n';
    if (mn < th && th < mx) {
        ldb tmp = min(t, mx - th);
        ans += tmp;
        ans += max((ldb)0, th + t - 2 * pi - mn);
    } else {
        if (th > mx) th -= 2 * pi;
        // cout << th << '\n';
        // cout << th + t << '\n';
        if (th + t < mn) {
        } else if (th + t > mx) {
            ans += mx - mn;
        } else {
            ans += th + t - mn;
        }
    }
    // cout << ans << '\n';
    printf("%.8LF", ans);
}
/*
3 1 0 1 1
1 2
2 1
2 2
*/