C / C++ / MFC

#include <iostream.h>

struct node
{
	int info;
	node *link;
};

void main()
{
	node *p;
        int s;
	node *create_list();
	void print_list(node *);
        int sum_of_even(node *);
	p=create_list();
	print_list(p);
        s=sum_of_even(p);
        cout<<"The sum of nodes with even values is: "<<s<<endl;
}

node *create_list()
{
	node *p, *q=NULL;
	int x;
	cout<<"Enter the elements of the list (enter \"-1\" without quotes for end)"<<endl;
	cin>>x;
	while(x!=-1)
	{
		p=new node;
		p->link=q;
		p->info=x;
		q=p;
		cin>>x;
	}
	return(p);
}

void print_list(node *p)
{
	cout<<"The list is: ";
	while(p!=NULL)
	{
		cout<<"->"<<p->info;
		p=p->link;
	}
	cout<<endl;
}

int sum_of_even(node *p)
{
	node *q, *q1;
	int sum=0;
	q=p->link;
	q1=q->link;
	while(p!=q)
	{
		if(q->info%2==0)
		{
			sum+=q->info;
		}
		q=q->link; //The error might be here
		q1=q1->link;//and here of course.
	}
	return (sum);
}

void CCalibracionDlg::BorrarRecta(int Rx,unsigned char D_Ry, unsigned char Vref)
{

CClientDC pDC(this) ;
float tgAng=0,Ry=0;			// float porque estas variables tienen cocientes		
int  x = 0 , y = 0 ,y_=0;	// int porque pueden ser mayor q 255
char multiplo=0;
unsigned char indice_recta=0, y_RectaVieja[300]; // con char alcanza
unsigned int pixel=0, PixelRectaVieja[300];		// int porque son de 32bit
pDC.SetWindowOrg(-168,-165);				// seteo el origen de coordenadas a ese punto, q es el centro de la grilla
.
.a lot of code that it isn't important for this issue
.
}

// sockDlg.cpp : implementation file

BOOL CsockDlg::OnInitDialog()
{
	.
        .
        .
	// TODO: Add extra initialization here
	int m_iPort = 4000;

	m_sConnectSocket.SetParent(this);      // Object of CMySocket derived from CAsyncSocket
	m_sListenSocket.SetParent(this);       // // Object of CMySocket derived from CAsyncSocket

	m_sListenSocket.Create(m_iPort);
	m_sListenSocket.Listen();

	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CsockDlg::OnAccept(void)
{
	//m_sListenSocket.Accept(m_sConnectSocket);
	AfxBeginThread(ThreadServer, this);
}

UINT CsockDlg::ThreadServer(LPVOID pParam)
{
	CsockDlg* C = (CsockDlg*)pParam;
	CAsyncSocket client;
	C->m_sListenSocket.Accept(client);
	//::Sleep(60000);
	return 0;
}