One simple error(IN DOS)

The following code has one simple error: Undefined simbol 'B'
can someone help me?????

PS: i am making a simple invader game. so far no bullet is being shot but the object will be.
_________________________________
#include <iostream.h>
#include <conio.h>
#include <stdlib.h>

int main()
{
{
int b = 0;//B is the number 0
int z = 25;
int w = 5;
gotoxy(z, w);
putch(b);//puts the variable B at z, w coordinates.
}
int x = 15;
int y = 25;
int a = 1;
while(a==1)
{
char cl = getch();
if (cl==77)
{
clrscr();
gotoxy(x++, y);
putch('Y');
gotoxy(x++, y);
}
if (cl==75)
{
clrscr();
gotoxy(x--, y);
putch('Y');
gotoxy(x--, y);
}
if (cl==32)
{
if (b==x, y-20)//THE ERROR IS OVER HERE!!!!!
{
clrscr();
gotoxy(x, y);
putch('@');
}
}
if (cl==27)
{
exit(0);
}
}
return 0;
}
____________________________________
How do you fix it??

Quote:

---

so far no bullet is being shot but the object will be.

---

I'm sorry, but i meant to say:
so far no bullet is being shot but the 'B' will be terminated.
:D

Maybe its just a typo but you cant have a ',' inside an if statement you proably want && (and) or ||(or)

Quote:

---

Maybe its just a typo but you cant have a ',' inside an if statement you proably want && (and) or ||(or)

---

Doesn't do anything: it still has some error

I tried to compile it without the y-20 in your if statement and I get an error that states:
implicit declaration of function `int gotoxy(...)'
implicit declaration of function `int clrscr(...)'

I thought this game wuz gonna b simple!!!!

the if statement has no idea what you want. Tell me in english what this line of code means:

Code:

---

if(b==x, y-20);

---

also, for putch(b), do this:

Code:

---

putch('b');

---

The if (b==x, y-20)
is supposed to check if the variable 'b' is at position x, y minus 20

change:

Code:

---

int main()
{
    {
        int b = 0;//B is the number 0
        int z = 25;
        int w = 5;
        gotoxy(z, w);
        putch(b);//puts the variable B at z, w coordinates.
    }

---

to

Code:

---

int main()
{
        int b = 0;//B is the number 0
        int z = 25;
        int w = 5;
        gotoxy(z, w);
        putch(b);//puts the variable B at z, w coordinates.

---

the brackets ({}) tell the compiler that the code between them only exists between them. So since the variabels that you set up in between the brackets can only exist between them you wouldn't be able to use the variables anywere else in you're code unless you changed it.

do the collision detection like this:

Code:

---

if(x==13 && y==13)
{//I am thinking that you are approaching a wall from the left
        gotoxy(x,y);
        putch(' ');
        x--;
        gotoxy(x,y);
        putch('@');
}

---

this says that if x=13 and y=13 then the '@' should move left one space so it doesn't go through the wall. Use for loops for this. Very useful for levels in your game.

trust me, I know. Here is a game I made about 10 months ago. I have the same game for windows, too. But this was one of my first games. All my other games I never give out cuz I convince myself they are never finished.