New guy Help- adding two numbers in Embedded C

i don't what is my mistake i am new to embedded c ,please help me

my code is:

#include <reg51.h>
#include <stdio.h>
extern unsigned int getnumber (void);
extern void output (unsigned int);

void main (void) {
unsigned int number1, number2; bit operation;
SCON = 0x50;
TMOD = 0x20;
TR1 = 1;
T1 = 1;
TH1 = 221;
printf ("hi yuvaraj");

while (1) {
number1 = getnumber ();
number2 = getnumber ();
printf ("Input operation: '+' (ADD) or '-' (SUB) ? "); operation = (getchar () == '+'); /* get operation */ output (operation ? (number1 + number2) /* perform operation */ : (number1 - number2) ); }
}