numbers <- c(1, 3, 2, 1, 3)
# The order of first occurrence is kept
unique_numbers <- unique(numbers)
# unique_numbers = 1 3 2
# fromLast keeps the last occurrences
unique_last <- unique(numbers, fromLast = TRUE)
# unique_last = 2 1 3
cat("unique_numbers =", unique_numbers, "\n")
cat("unique_last =", unique_last, "\n")