#include <stdio.h>
#include <iostream>
#include <algorithm>
#include <set>
#include <map>
#include <vector>
#include <string>
#include <math.h>
#include <utility>

using namespace std;

void rot(double &x, double &y, double angle)
{
	double x2 = x*cos(angle) - y*sin(angle);
	double y2 = x*sin(angle) + y*cos(angle);
	x=x2;
	y=y2;
}

double det(double a, double b, double c, double d)
{
	return a*d - b*c;
}

void run()
{
	int T, k1, k2;
	cin >> T >> k1 >> k2;
	if(T==0 && k1==0 && k2==0)
		exit(0);

	k1 = k1%T;
	k2 = k2%T;
	double x1,y1,x2,y2,x3,y3;
	cin >> x1 >> y1 >> x2 >> y2 >> x3 >> y3;
	rot(x2,y2, -double(k1)/double(T)*double(2*M_PI));
	rot(x3,y3, -double(k1+k2)/double(T)*double(2*M_PI));

//	printf("(%.2g,%.2g), (%.2g,%.2g), (%.2g,%.2g)\n", x1,y1, x2,y2, x3,y3);

	// first segment
	double xa = (x1+x2)*0.5, ya = (y1+y2)*0.5;
	double dxa = (y1-ya), dya = (xa-x1);
//	printf("(%.2g,%.2g) --> (%.2g,%.2g)\n", xa,ya,dxa,dya);

	// second segment
	double xb = (x2+x3)*0.5, yb = (y2+y3)*0.5;
	double dxb = (y3-yb), dyb = (xb-x3);
//	printf("(%.2g,%.2g) --> (%.2g,%.2g)\n", xb,yb,dxb,dyb);

	double A = dxa, B = -dxb, C = xb-xa;
	double D = dya, E = -dyb, F = yb-ya;
	double d = det(A,B,D,E);
//	if(d < 1e-7) cerr << "singular!\n";
	double a = det(C,B,F,E)/d;
	double b = det(A,C,D,F)/d;

	double X = xa+a*dxa;
	double Y = ya+a*dya;
//	printf("(%.2g,%.2g)\n", X,Y);

	cout << (int)(0.5 + sqrt(X*X + Y*Y)) << endl;
}

int main()
{
	while(1) run();
}