Problem with moving character around(using array for map)

I am using an array for my background, if you compile you will see what I mean... I want it to put the char back where it was when the smiley moves forward, but when I compile its putting it one step down, or not at all :(. If anyone can tell me whats wrong I would be grateful.. Here is the code:

Code:

---

#include <iostream>
#include <windows.h>
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
int ch;
static int get_code ( void )
{
  int ch = getch();

  if ( ch == 0 || ch == 224 )
    ch = 256 + getch();

  return ch;
}

enum
{
  KEY_ESC    = 27,
  ARROW_UP    = 256 + 72,
  ARROW_DOWN  = 256 + 80,
  ARROW_LEFT  = 256 + 75,
  ARROW_RIGHT = 256 + 77
};








using namespace std;

int x=0,y=0;
void gotoxy(int x, int y)           
{
        HANDLE hConsoleOutput;
hConsoleOutput = GetStdHandle(STD_OUTPUT_HANDLE);
        COORD dwCursorPosition;

        dwCursorPosition.X = x;
        dwCursorPosition.Y = y;
       
        SetConsoleCursorPosition(hConsoleOutput,dwCursorPosition);
}



char map[100][100] = {"+++++++++++++++++++++++++++++++++++++++++++++++++++++++++",
                                      "---------------------------------------------------------",
                                      "fffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
                      "rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr"
} ; 
int main ()
{
       
       
        gotoxy(0,0);
        for (int j = 0; j < 4; j++)
        {
               
                cout << map[j] << endl;
               
        }
       
        while ( ( ch = get_code() ) != KEY_ESC ) {
    switch ( ch ) {
               
    case ARROW_UP:
      gotoxy(x,y--);
          putchar(1);
      gotoxy(x,y++);
          putchar(map[y][x]);
          gotoxy(x,y--);
          break;
    case ARROW_DOWN:
      gotoxy(x,y++);
          putchar(1);
          gotoxy(x,y--);
          putchar(map[y][x]);
      gotoxy(x,y++);
      break;
    case ARROW_LEFT:
      gotoxy(x--,y);
          putchar(1);
          gotoxy(x++,y);
          putchar(map[y][x]);
          gotoxy(x--,y);
          break;
    case ARROW_RIGHT:
      gotoxy(x++,y);
          putchar(1);
          gotoxy(x--,y);
          putchar(map[y][x]);
          gotoxy(x++,y);
         
      break;
    }
        }

               
               

         
                 
                 

   

       
  return 0;
}

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First, you are using the postfix autoincrement and decrement operators where you should be using prefix notation, (i.e. in your switch change x++ to ++x and the same with the minuses and the operations on y). Once you've done that, as long as you start with, for example the Right Arrow case, it sort of works.

Your other problem is that you're position values can go negative and you are not handling that. If you start with the Left Arrow for example, it will screw up.