Simpson.cpp

#include <bits/stdc++.h>
using namespace std;
typedef double ld;
ld a,b,c,d;
inline ld f(ld x) {
	return (c*x+d)/(a*x+b);
}
inline ld simpson(ld l, ld r, ld fl, ld fr, ld fm) {
    return (r - l) * (fl + fr + 4 * fm) / 6;
}

inline ld asr(ld l, ld r, ld eps, ld fl, ld fr, ld fm) {
    ld flm = f((l + (l+r)/2) / 2), frm = f((r + (l+r)/2) / 2);
    ld L = simpson(l, (l+r)/2, fl, fm, flm), R = simpson((l+r)/2, r, fm, fr, frm), A = simpson(l, r, fl, fr, fm);
    if (fabs(L + R - A) <= 15 * eps) return L + R + (L + R - A) / 15;
    return asr(l, (l+r)/2, eps / 2, fl, fm, flm) + asr((l+r)/2, r, eps / 2, fm, fr, frm);
}
inline ld cal(ld l,ld r){
	return asr(l,r,1e-10,f(l),f(r),f((l+r)/2));
}
int main() {
    
    return 0;
}