digraph {
    "empty" -> "col 1\nrow 1"
    "empty" -> "col 1\nrow 2"
    "empty" -> "col 1\nrow 3"
    "empty" -> "col 1\nrow 4"
    "empty" -> "col 1\nrow 5"
        "col 1\nrow 5" -> "col 2\nrow 1"
        "col 1\nrow 5" -> "col 2\nrow 2"
        "col 1\nrow 5" -> "col 2\nrow 3"
        "col 1\nrow 5" -> "col 2\nrow 4"
        "col 1\nrow 5" -> "col 2\nrow 5"
        "col 1\nrow 5" -> "col 2\nrow 6"
        "col 1\nrow 5" -> "col 2\nrow 7"
        "col 1\nrow 5" -> "col 2\nrow 8"
    "empty" -> "col 1\nrow 6"
    "empty" -> "col 1\nrow 7"
    "empty" -> "col 1\nrow 8"
}