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int _di_ = 0;

void pokeb(int a, int b, char c)
{
    asm mov ax, [a];
    asm mov es, ax;
    asm mov di, [b];
    asm mov al, [c];
    asm mov [es:di], al;
}

char peekb(int a, int b)
{
    char c;
    asm mov ax, [a];
    asm mov es, ax;
    asm mov di, [b];
    asm mov al, [es:di];
    asm mov [c], al;
    return c;
}

void outp(int a, char b)
{
    asm mov dx, [a];
    asm mov al, [b];
    asm out dx, al;
}

char inp(int a)
{
    char b;
    asm mov dx, [a];
    asm in al, dx;
    asm mov [b], al;
    return b;
}

void gotoxy(int a)
{
    char b;
    char c;
    _di_ = a * 2;
    asm mov ax, [a];
    asm mov [b], al;
    asm mov [c], ah;
    outp(0x3d4, 0xf);
    outp(0x3d5, b);
    outp(0x3d4, 0xe);
    outp(0x3d5, c);
}

void clrscr()
{
    int a;
    for (a = 0x0; a <= 0xf00;)
    {
	pokeb(0xb800, a, ' ');
	a++;
	pokeb(0xb800, a, 0x1f);
	a++;
    }
    gotoxy(_di_ / 2);

}

void putch(char a)
{
    int b;
    if (_di_ == 0xfa0)
    {
	for (b = 0x0; b <= 0xf00; b++)
	{
	    pokeb(0xb800, b, peekb(0xb800, b + 0xa0));
	}
	for (b = 0xf00; b <= 0xfa0;)
	{
	    pokeb(0xb800, b, 0x20);
	    b++;
	    pokeb(0xb800, b, 0x1f);
	    b++;
	}
	_di_ = 0xf00;
    }
    if (a == '\n')
    {
	_di_ = _di_ - _di_ % 0xa0 + 0xa0;
    }
    else if ((a >= 0x20) && (a <= 0x7e))
    {
	pokeb(0xb800, _di_, a);
	_di_++;
	pokeb(0xb800, _di_, 0x1f);
	_di_++;
    }
    gotoxy(_di_ / 2);
}

void puts(char *a)
{
    while (*a != 0)
    {
	putch(*a);
	a++;
    }
}

void main(void)
{
    clrscr();
    gotoxy(988);
    puts("Matias Sebastian Beretta");

    asm mov ah, 0x0;
    asm int 0x16;
}