카타 7급 How Green Is My Valley?

2 R

makeValley <- function(arr) {
  len <- length(arr)
  if(len<1) return(c())
  a <- sort(arr)
  left <- a[seq(len,1,by=-2)]
  right <- a[seq(1+len%%2,len,by=2)]
  return(c(left,right))
}

makeValley <- function(arr) {
  n <- length(arr)%/%2
  odd <- length(arr)%%2
  arr <- sort(arr, decreasing =T)
  return(c(arr[2*0:(n- 1 + odd)+1],sort(arr[2*1:n])))
}