#include <iostream>
#include <math.h>
using namespace std;
int N;
double x0,xn,h;
double g(int i)
{
    return x0+i*h;
}
double p(int i)
{
    return 0;
}
double q(int i)
{
    return tan((x0+i*h)-1);
}
double A(int i)
{
    return 1+(h/2)*p(i);
}
double B(int i)
{
    return -2+pow(h,2)*q(i);
}
double C(int i)
{
    return 1-(h/2)*p(i);
}
double l(int i)
{
    if (i==0) return 0;
    else return -A(i)/(B(i)+C(i)*l(i-1));
}
double k(int i)
{
    if (i==0) return x0;
    else return (pow(h,2)*g(i)-C(i)*k(i-1))/(B(i)+C(i)*l(i-1));
}
double u(int i)
{
    if (i==N){cout<<"\n"<<xn; return xn;}
    else{double tmp=l(i)*u(i+1)+k(i); cout<<"\n"<<tmp; return tmp  ;}
}


int main ()
{

    cout << "N: ";
    cin >>N;
    cout << "\n a:";
    cin >> x0;
    cout<< "\n b:";
    cin>>xn;
    h=(xn-x0)/N;
    cout <<endl<< u(0);
    return 0;
}