problema con getch

[Tikitios]

No me funciona, mira el codigo:

#include <iostream>
#include <stdlib.h>
#include <conio.h>

using namespace std;

void sumar();
void restar();
void multiplicar();
void dividir();

char x;
long a, b, total;
float c, d, totald;

void sumar() {
cout << "Introduce un numero para sumar.\n";
cin >> a;
cout << "Ahora introduce el otro numero para sumar.\n";
cin >> b;
cout << "La suma de "<< a <<" y "<< b <<" es "<< a + b <<"\n";
}

void restar() {
cout << "Introduce un numero para ser restado.\n";
cin >> a;
cout << "Ahora introduce el numero que restara a "<< a <<".\n";
cin >> b;
cout << ""<< a <<" disminuido en "<< b <<" es "<< a - b <<".\n";
}

void multiplicar() {
cout << "Introduce un numero para multiplicarlo.\n";
cin >> a;
cout << "Ahora introduce el otro numero para multiplicarlo con "<< a <<".\n";
cin >> b;
cout << ""<< a <<" por "<< b <<" es "<< a * b <<"\n";
}

void dividir() {
cout << "Introduce un numero para dividirlo.\n";
cin >> c;
cout << "Ahora introduce el numero que dividira a "<< c <<".\n";
cin >> d;
totald = (float) c / d;
printf ("%.1f dividido en %.1f es %.3f \n" ,c,d, totald);
}

void bucleMain() {

cout << "\n\nIntroduce '+' o 's' si quieres sumar\n";
cout << "Introduce '-' o 'r' si quieres restar\n";
cout << "Introduce '*' o 'm' si quieres multplicar\n";
cout << "Introduce '/' o 'd' si quieres dividir\n";
cout << "Si oprimes otra tecla me cerrare\n";

getch(x);
switch (x) {
case 'S': case 's': case '+':
sumar();
break;
case 'R' : case 'r': case '-':
restar();
break;
case 'M' : case 'm': case '*':
multiplicar();
break;
case 'D' : case 'd': case '/':
dividir();
break;
case '\n' : case ' ':
break;

default : exit(0);
break;
}

}
main()
{
cout << "Esta es la Calculadora 1.0 \n";
do { bucleMain(); }
while(1);
system("PAUSE");
return 0;
}

Y aqui esta mi conio:

/*
* conio.h
* This file has no copyright assigned and is placed in the Public Domain.
* This file is a part of the mingw-runtime package.
* No warranty is given; refer to the file DISCLAIMER within the package.
*
* Low level console I/O functions. Pretty please try to use the ANSI
* standard ones if you are writing new code.
*
*/

#ifndef _CONIO_H_
#define _CONIO_H_

/* All the headers include this file. */
#include <_mingw.h>

#ifndef RC_INVOKED

#ifdef __cplusplus
extern "C" {
#endif

_CRTIMP char* __cdecl _cgets (char*);
_CRTIMP int __cdecl _cprintf (const char*, ...);
_CRTIMP int __cdecl _cputs (const char*);
_CRTIMP int __cdecl _cscanf (char*, ...);

_CRTIMP int __cdecl _getch (void);
_CRTIMP int __cdecl _getche (void);
_CRTIMP int __cdecl _kbhit (void);
_CRTIMP int __cdecl _putch (int);
_CRTIMP int __cdecl _ungetch (int);


#ifndef _NO_OLDNAMES

_CRTIMP int __cdecl getch (void);
_CRTIMP int __cdecl getche (void);
_CRTIMP int __cdecl kbhit (void);
_CRTIMP int __cdecl putch (int);
_CRTIMP int __cdecl ungetch (int);

#endif /* Not _NO_OLDNAMES */


#ifdef __cplusplus
}
#endif

#endif /* Not RC_INVOKED */

#endif /* Not _CONIO_H_ */