In R or Rstudio:

Write a function called once_sum with arguments:

nums: a numeric vector of any length greater than or equal to 1.

The function should return a numeric vector of length one that contains the sum of values which appear exactly once in the vector nums.

Ex:

some_nums = c(1, 2, 3, 4, 5, 5) once_sum(nums = some_nums)

returns 10