calculating a simple math algorithm

[expert4c]

Hi every one, I have to design a simple algorithm and it is to calculate roots of a quadratic equation, it has to read data, post errors if they are not suitable and also it has to use header files to manage errors, anyone here I can find?

[Moschops]

http://rosettacode.org/wiki/Roots_of_a_quadratic_function

[expert4c]

In fact I have 2 problems, I need to use hear files but my visual studio does not work, my other problem is that I wrote the code without headers but it has a lot of errors.
The code is as follows:

#include<conio.h>
#include<string.h>
#include<time.h>
#include<string>
#include<iostream>
using namespace std; 
#include<fstream>
#include "stdio.h"

//try to execute the following code
//i hope it will work properly

#include<process.h>
int main()
{
int a,b,c,discriminant;
float r1,r2,d,x1,x2;
cout<<"enter the values of a,b,c";
cin>>a>>b>>c;
if(a==0)
{
	d=-c/b;
cout<<"matherror, this is not a quadratic equation and root is equal to:"<<d;
goto BB;

}
discriminant=((b*b)-4*a*c);
if(discriminant>0)
{
x1=(-1*b+sqrt(discriminant))/(2*a);
x2=(-1*b-sqrt(discriminant))/(2*a);
}
else if(discriminant==0)
{
r1=r2=(-1*b)/(2*a);
}
else
{
cout<<"matherror, this equation does not have real answer";


}
cout<<"x1="<<r1<<"\n";
cout<<"x2="<<r2<<"\n";

cout<<"equation="<<a<<"x2"<<<<"+"<<b<<"x"<<"+"<<c<<"\n";
BB:
return 0;
}

When I run it I see the following errors:
c:\program files\microsoft visual studio 10.0\vc\include\iostream(25): error C2146: syntax error : missing ';' before identifier 'cin'
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(25): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int

1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(27): error C2146: syntax error : missing ';' before identifier 'cerr'
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(27): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
pe specifier - int assumed. Note: C++ does not support default-int
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(32): error C2146: syntax error : missing ';' before identifier 'wcerr'
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(32): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(33):
1>c:\program files\microsoft visual studio 10.0\vc\include\iostream(33): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\program files\microsoft visual studio 10.0\vc\include\cmath(8): error C2297: '<<' : illegal, right operand has type 'const char [4]'
1>c:\program files\microsoft visual studio 10.0\vc\include\cmath(8): warning C4552: '<<' : operator has no effect; expected operator with side-effect
1>c:\program files\microsoft visual studio 10.0\vc\include\iosfwd(635): error C2378: 'std::istream' : redefinition; symbol cannot be overloaded with a typedef
1> c:\program files\microsoft visual studio 10.0\vc\include\iostream(26) : see declaration of 'std::ostream'
1>c:\program files\microsoft visual studio 10.0\vc\include\iosfwd(655): error C2378: 'std::wistream' : redefinition; symbol cannot be overloaded with a typedef
1> c:\program files\microsoft visual studio 10.0\vc\include\iostream(30) : see declaration of 'std::wistream'
1>c:\program files\microsoft visual studio 10.0\vc\include\iosfwd(656): error C2378: 'std::wostream' : redefinition; symbol cannot be overloaded with a typedef
1> c:\program files\microsoft visual studio 10.0\vc\include\iostream(31) : see declaration of 'std::wostream'
1>c:\program files\microsoft visual studio 10.0\vc\include\cmath(6): error C2084: function 'int main(void)' already has a body
1> c:\program files\microsoft visual studio 10.0\vc\include\cmath(5) : see previous definition of 'main'
1>c:\program files\microsoft visual studio 10.0\vc\include\cmath(8): error C2297: '<<' : illegal, right operand has type 'const char [4]'
1>c:\program files\microsoft visual studio 10.0\vc\include\cmath(8): warning C4552: '<<' : operator has no effect; expected operator with side-effect
1>c:\users\me\documents\visual studio 2010\projects\genethic\genethic\genethic.cpp(19): error C2297: '<<' : illegal, right operand has type 'const char [26]'
1>c:\users\me\documents\visual studio 2010\projects\genethic\genethic\genethic.cpp(24): error C2297: '<<' : illegal, right operand has type 'const char [66]'
1>c:\users\me\documents\visual studio 2010\projects\genethic\genethic\genethic.cpp(24): error C2297: '<<' : illegal, right operand has type 'float'
1>c:\users\me\documents\visual studio 2010\projects\genethic\genethic\genethic.cpp(24): warning C4552: '<<' : operator has no effect; expected operator with side-effect
1>c:\users\me\documents\visual studio 2010\projects\genethic\genethic\genethic.cpp(31): error C3861: 'sqrt': identifier not found

I tried to delete repeatitions from errors.

[Moschops]

I've seen something like this before. It turned out to be a bad upgrade from one version of VS to another and a fumbled "conversion" of some project format. I think the solution was to just uninstall everything relating to VS and do a fresh, clean install.

[expert4c]

I did not upgrade it but it seems that I need to reinstall it but I think there are some ways to prevent re-installation.

[LGonzales]

You might want to try doing a simple "Hello World" program to see if even that compiles.

If that fails then your PATH might be wrong, or you have duplicate/and-or missing files in several INCLIDE and LIB paths that can cause problems when compiling.
I'm saying this becuase I see it has problems recognizing the 'cin' and '<< ' identifiers.

Despite these errors there are only two errors that you should fix,
line 46 you have two "<<" after the "x2" string,
and you need to include <math.h> if you want to use the sqrt function.

[TheIdeasMan]

My 2 cents worth:

Why stdio.h?

Don't use goto !!

[LGonzales]

From what I remember, thats standard i/o. Isnt that a C program?

I think you have to much in your includes section. The only one i see that you need is
#include <iostream>