"sort"

	for _, tck := range tickets {
		tmp := tck.row*8 + tck.col
		if tmp > max {
			max = tmp

	ids := make([]int, len(tickets))
	for i, tck := range tickets {
		ids[i] = tck.row*8 + tck.col
		if ids[i] > max {
			max = ids[i]

	sort.Ints(ids)
	for i, seat := range ids {
		if seat != i+99 {
			log.Println("MISSING:", seat-1)
			break
		}
	}