{
	for (i = 1; i < length; i++) {
		c1 = c2;
		c2 = c3;
		c3 = c4;
		c4 = substr($1, i, 1);
		if (c1 == c2 || c1 == c3 || c1 == c4) continue;
		if (c2 == c3 || c2 == c4) continue;
		if (c3 == c4) continue;
		if (i < 4) continue;
		print i;
		break;
	}
}