Define a function int getRoots(double a, double b, double c, double & s1, double & s2) that solves a quadatic equation with coefficients a, b and c. If there are no real roots than the return value will be 0 and the values of s1 and s2 will be left as is. If there is one real solution the return value will be 1 and s1 will be set to the solution with s2 left as is. If there are two real solutions then the return value will be 2 with s1 set to the smaller solution and s2 set to the bigger solution.