Either 'start' or 'end'. If 'start' the flag will indicate who is
alive at the start of the episode. If 'end' it will indicate who is alive at
the end of the episode i.e. after tribal council.
library(survivoR)
library(dplyr)
# at the end of the episodestill_alive("US47", 12)
# at the start of the episodestill_alive("US47", 12, .at = "start")