#include <stdio.h>

int main()
{
	double x[500];
	double y[500];
	double sx, sy, sxx, sxy;
	double a, b;
	int i, n;

	for (i = 0; i < 500; i++) {
		scanf("%lf%lf", &x[i], &y[i]);
		if (x[i] == 0.0) break;
	}
	n = i;
	sx = sy = sxx = sxy = 0;
	for (i = 0; i < n; i++) {
		sx += x[i];
		sy += y[i];
		sxx += x[i] * x[i];
		sxy += x[i] * y[i];
	}
	a = (n * sxy - sx * sy) / (n * sxx - sx * sx);
	b = (sxx * sy - sxy * sx) / (n * sxx - sx * sx);
	printf("a=%f b=%f\n", a, b);
	return 0;
}