C++ help?

hey guys what's wrong with this codes? =/

#include <stdio.h>
#include <math.h>

double f(double x);
double dfdx(double x);
int main(){
	int i=0;
	double x_eski = 10.0, // tahmini kok, x0
		   x_yeni = 10.0,
		   eps = 1.0e-3, // yakinsama kriteri
		   hata = 100.0; // buyuk bir sayi
		   
	printf("%d %e\n", i, x_yeni);
	
    while(hata > eps && i < 30){
            x_yeni=x_eski - f(x_eski)/dfdx(x_eski);
            i++;
            printf("%d %e\n", i, x_yeni);
	    hata = fabs(x_yeni - x_eski) / fabs(x_eski);
	    x_eski = x_yeni;
	}

	if(i == 30)
           printf("Raphson Newton yinelemesi yakinsamadý!\n");
	return 0;
}

double f(double x){
	return(x*x*x + x*x + x - 1.0);
}

double dfdx(double x){
	return(3.0*x*x + 2.0*x + 1.0);
}

Code (markup):

 

give us a clue - does it not compile or are we looking for a runtime error?

 

If this is C++ code, I suggest you avoid C style output(printf), use C++ style output(cout<<), do not forget include<iostream>, and use english for comments please...XD, We can not even read it...

 

That is C style, not C++

If it's just one main file, why bother defining prototypes, just do implementations at top, save a few lines.

 

The above code is not c++.It is just c code.There is no class in it. There is no printf function in c++ instead it has cout function.If it is c++ their should be included include<iostream> library function at header. so it not a c++ code. i suggset you to rename it has c code.