#include <stdio.h>
char gif [4096*1024];
int main (void) {
int screenwidth;
int screenheight;
int pos;
strcpy (gif, "GIF87a");
screenwidth = 255;
screenheight = 255;
pos = strlen ("GIF87a");
gif [pos+0] = 0
gif [pos+1] = screenwidth;
gif [pos+2] = 0
gif [pos+3] = screenheight;
pos += 4;
}