on rightclick:
    block is a sign
    line 2 of clicked block is "-checkpoint-"
    line 3 of clicked block is "[rightclick]"
    set {checkpoint.%player%} to location of player
    message "&6チェックポイントを設定しました!"
    if player has permission "skript.admin":
        message "&7Location of player"

on rightclick with nether star:
    cancel event
    if clicked block is sign:
        stop
    if {checkpoint.%player%} is set:
        teleport player to {checkpoint.%player%}
    else:
message "&cチェックポイントが設定されていません!"