forum.alglib.net

hi every body i am learning c++ language as well as the alglib...
i started with a project and i can compile every individual files in my project,
however once i want to compile the whole project, the Dev-C++ gives me error like these...

these are some parts on my program...

#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
#include <math.h>
#include "specialfunctions.h"
using namespace std;
using namespace alglib;
int main()
{

.
.
.
.
qchisq=invchisquaredistribution(double (nvar),delta);
.
.
.
return 0;
}

thank you!