10760.cpp

#include <bits/stdc++.h>

using namespace std;

#define EPS 1e-8

struct vec
{
	double x, y;
};
struct seg
{
	vec a, b, d;
};

int zero(double x)
{
	return fabs(x) < EPS;
}
int zero(vec v)
{
	return zero(v.x) && zero(v.y);
}
int zero(seg s)
{
	return zero(s.a) && zero(s.b);
}
double operator*(vec &a, vec &b)
{
	return a.x * b.x + a.y * b.y;
}
double skew(vec a, vec b)
{
	return a.x * b.y - a.y * b.x;
}
vec operator-(vec &a, vec &b)
{
	vec c = {a.x - b.x, a.y - b.y};
	return c;
}
double sq(double x)
{
	return x * x;
}
double norm(vec v)
{
	return sqrt(v * v);
}

int main()
{
	seg s1, s2;
	double pi = 2. * acos(0.);
	for (;;)
	{
		int i = scanf("%lf%lf%lf%lf%lf%lf%lf%lf",
									&s1.a.x, &s1.a.y, &s2.a.x, &s2.a.y,
									&s1.b.x, &s1.b.y, &s2.b.x, &s2.b.y);
		if (i < 8 || (zero(s1) && zero(s2)))
		{
			break;
		}
		s1.d = s1.b - s1.a;
		s2.d = s2.b - s2.a;
		if (zero(s1.a - s2.a) && zero(s1.b - s2.b))
		{
			printf("No move.\n");
			continue;
		}
		if (zero(s1.d - s2.d))
		{
			printf("Translation by vector <%.1f,%.1f>.\n",
						 s2.a.x - s1.a.x + EPS, s2.a.y - s1.a.y + EPS);
			continue;
		}
		double a1 = 2 * s2.a.x - 2 * s1.a.x, b1 = 2 * s2.a.y - 2 * s1.a.y;
		double c1 = sq(s2.a.x) - sq(s1.a.x) + sq(s2.a.y) - sq(s1.a.y);
		double a2 = 2 * s2.b.x - 2 * s1.b.x, b2 = 2 * s2.b.y - 2 * s1.b.y;
		double c2 = sq(s2.b.x) - sq(s1.b.x) + sq(s2.b.y) - sq(s1.b.y);
		double d = a1 * b2 - a2 * b1;
		if (zero(d))
		{
			a2 = s1.a.y - s1.b.y;
			b2 = s1.b.x - s1.a.x;
			c2 = s1.a.x * a2 + s1.a.y * b2;
			d = a1 * b2 - a2 * b1;
		}
		vec O = {(c1 * b2 - b1 * c2) / d, (a1 * c2 - c1 * a2) / d};
		vec U = s1.a - O, V = s2.a - O;
		double t = U * V / (norm(U) * norm(V));
		t = acos(t) * 180 / pi;
		if (skew(U, V) < 0.)
		{
			t = -t;
		}
		while (t < -EPS)
		{
			t += 360;
		}
		while (t > 360 - EPS)
		{
			t -= 360;
		}
		if (zero(t))
		{
			t = EPS;
		}
		printf("Rotation around (%.1f,%.1f) by %.1f degrees counterclockwise.\n", O.x + EPS, O.y + EPS, t);
	}
	return 0;
}