#!/usr/bin/env octave
disp ("Solve quadratic equation a*x^2 + b*x + c = 0");
a = input ("a = ");
while (a == 0)
  disp ("a must be nonzero");
  a = input ("a = ");
end
b = input ("b = ");
c = input ("c = ");

sd = sqrt(b*b - a*c*4);
disp ("The two solutions of the given quadratic equation are:");
x0 = (-b - sd) / a / 2
x1 = (-b + sd) / a / 2