/*
 * Program to find real roots of quadratic equation.
 */
#include <stdio.h>
#include <math.h>

int main(void) {
	printf("enter coefficients a, b, c\n");
	double a, b, c;
	if (scanf("%lf %lf %lf", &a, &b, &c) != 3) {
		printf("invalid input\n");
		return 1; /* bail out of program */
	}

	double d = b*b - 4*a*c;
	if (d < 0) {
		printf("no real roots\n");
		return 0;
	} 

	if (a != 0) {
		double r1 = (-b + sqrt(d))/(2*a);
		double r2 = (-b - sqrt(d))/(2*a);

		printf("roots for a = %f, b = %f, c = %f are %f, %f\n",
				a, b, c, r1, r2);
	} else if (b != 0) {
		double r1 = -c / b;
		printf("root for a = %f, b = %f, c = %f is %f\n",
				a, b, c, r1);
	} else {
		if (c != 0) {
			printf("no solutions\n");
		} else {
			printf("infinitely many solutions\n");
		}
	}
	return 0;

}