#include <stdio.h>
#include <conio.h>
#include <string.h>
#include <math.h>
   int sign, sum=0, j, i=0, num;
   char arr={"\0"}, ch;
   clrscr();
   for (i=0 ; arr(i-1)!= '+' ; i++)
    {
     arr(i) = getch ();
     putch(arr(i));
    }//end for

for (i=0 ; arr(i-1)!= '+' || arr(i-1) !='-' ; i++)