#include <iomanip>#include <cassert>#include <cstdio>#include <cstring>#include <cmath>#include <iostream>#include <algorithm>using namespace std;const double EPS = 1e-8;const double PI = acos(-1.0);inline int sgn(double d) { if (fabs(d)<EPS) return 0; return d>0?1:-1;}struct sp { double x, y, z; sp() {} sp(double a, double b, double c): x(a), y(b), z(c) {} void write() { printf("%f %f %fn", x, y, z); }};sp operator-(const sp &u, const sp &v) { return sp(u.x-v.x, u.y-v.y, u.z-v.z);}double dot(const sp &u, const sp &v) { return u.x*v.x+u.y*v.y+u.z*v.z;}sp det(const sp &u, const sp &v) { return sp(u.y*v.z-v.y*u.z, u.z*v.x-u.x*v.z, u.x*v.y-u.y*v.x);}double nrm(const sp &u) { return sqrt(u.x*u.x+u.y*u.y+u.z*u.z);}double dis(const sp &u, const sp &v) { double dx = u.x-v.x; double dy = u.y-v.y; double dz = u.z-v.z; return sqrt(dx*dx+dy*dy+dz*dz);}double ang(const sp &u, const sp &v) { double d = dot(u, v); return acos(d/(nrm(u)*nrm(v)));}double r, h, as, ns, at, nt, R;sp s, t, hmr, mdk;double a, b, c, tmp;bool quad(double a, double b, double c, double &x1, double &x2) { double delta = b*b-4*a*c; if (sgn(delta)<=0) return 0; x1 = (-b+sqrt(delta))/(2*a); x2 = (-b-sqrt(delta))/(2*a); return 1;}bool coplane(const sp &a, const sp &b, const sp &c, const sp &d) { return sgn(dot(det(c-a, b-a), d-a))==0;}bool inside(const sp &s, const sp &p, const sp &t) { return sgn(dot(det(s,p),det(s,t)))>=0 && sgn(dot(det(p,t),det(s,t)))>=0;}int main() { while (cin>>r>>h>>as>>ns>>at>>nt) { if (sgn(as)==0 && sgn(at)==0) { puts("100.000"); continue; } as += PI/2; at += PI/2; ns += PI; nt += PI; R = r+h; s = sp(R*sin(as)*cos(ns), R*sin(as)*sin(ns), R*cos(as)); t = sp(R*sin(at)*cos(nt), R*sin(at)*sin(nt), R*cos(at)); a = s.y*t.z-s.z*t.y; b = s.z*t.x-s.x*t.z; c = s.x*t.y-s.y*t.x; tmp = -sqrt(R*R-r*r); hmr.z = mdk.z = tmp; assert(sgn(a)!=0 || sgn(b)!=0); if (sgn(b)) { if (quad(a*a+b*b, 2*a*c*tmp, c*c*(R*R-r*r)-b*b*r*r, hmr.x, mdk.x)) { hmr.y = (-c*tmp-a*hmr.x)/b; mdk.y = (-c*tmp-a*mdk.x)/b; } else { puts("100.000"); continue; } } else { if (quad(a*a+b*b, 2*b*c*tmp, c*c*(R*R-r*r)-a*a*r*r, hmr.y, mdk.y)) { hmr.x = (-c*tmp-b*hmr.y)/a; mdk.x = (-c*tmp-b*mdk.y)/a; } else { puts("100.000"); continue; } } int cnt = 0; if (inside(s, hmr, t)) ++cnt; if (inside(s, mdk, t)) ++cnt; double tot=ang(s, t), dark; if (cnt==0) { if (inside(hmr, s, mdk) && inside(hmr, t, mdk)) dark = tot; else dark = 0; } else if (cnt==1) { if (inside(s, mdk, t)) swap(hmr, mdk); assert(inside(s, hmr, t)&&!inside(s, mdk, t)); if (inside(hmr, s, mdk)) dark = ang(hmr, s); else dark = ang(hmr, t); } else dark = ang(hmr, mdk); double ans = (1-dark/tot)*100; printf("%.3fn", ans); } return 0;}
