Finding the root of a "real" quadratic equation

[OxBADC0DE]

We were given an assignment yesterday to have it submitted today,i did the solution to it only to find it working abnormally. The question was to find the root of a simple quadratic equation(the quoted "real" is just to scare the heck outta us"
here's my code which runs fine,no error but the results looks like 1.#ID,kinda weird

#include<iostream>
#include<math.h>
using namespace std;
int main(){
    signed int a,b,c,e;
    float d,f,g;
    cout<<"Enter the value of a: ";
    cin>>a;
    cout<<"B here: ";cin>>b;
    cout<<"C here: ";cin>>c;
    d=sqrt((b*b)-(4*a*c));
    e=(-1*b);
    f=(e+d)/(2*a);
    g=(e-d)/(2*a);
    cout<<"The root of the quadratic equation is "<<f
    <<" and "<<g<<endl;
    system("pause");
    return 0;
}

[long double main]

It works fine for me...

Enter the value of a: 2
B here: 5
C here: -2
The root of the quadratic equation is 0.350781 and -2.85078
Press any key to continue . . .

The only thing you might want to do is check to make sure the roots are real, or you'll get NaNs in your output.
Oh, and #include <cstdlib> because you're using system("pause").
(or, preferably, use something other than system() )

[naraku9333]

Agreed, it works fine for simple equations with real roots, what input are you testing?

[OxBADC0DE]

@longdoublemain...thnx for testing,I'll include the header file,see if it works
@naraku thnx i used Any! Starting with any random variable entered thru' your keyboard.But when i tried something like say,a=1,b=5,c=6(just for example),what i get is -1.#1D and 1.#1N which is the weird part for me. For emphasis sakes,i use DevC++4.9.9

[naraku9333]

With that input I get

Enter the value of a: 1
B here: 5
C here: 6
The root of the quadratic equation is -2 and -3
Press any key to continue . . .

Perhaps an issue with DevC++ which is quite outdated.

[OxBADC0DE]

Try a=9,b=1 and c=9

[long double main]

Enter the value of a: 9
B here: 1
C here: 9
The root of the quadratic equation is nan and nan
Press any key to continue . . .

You didn't check for nonreal roots (b^2 - 4ac must be >= 0).

[OxBADC0DE]

Yeah right but please how do i go about that?a code segment please?

[long double main]

After you have your a, b, and c from the user, just check if b^2 - 4ac < 0, and if it is, print an error message and quit.

if (b*b - 4*a*c < 0)
    cout << "Nonreal roots!" << endl;
else
{
    // calculate roots here... 

[OxBADC0DE]

You've been so helpful buddy,appreciate it alot.Thnx