카타 7급 Exes and Ohs

2 R

xo <- function(s){
  v <- unlist(strsplit(tolower(s),""))
  sum(v == "o") == sum(v == "x")
}

xo <- function(s){
  s <- tolower(s)
  nchar(gsub("x","",s)) == nchar(gsub("o","",s))
}

xo <- function(s){
  v <- unlist(strsplit(tolower(s), ""))
  length(grep("x",v,ignore.case=TRUE)) == length(grep("o",v,ignore.case=TRUE))
}

xo <- function(s){
  v = unlist(strsplit(s,""))
  sum(v %in% c("x","X")) == sum(v %in% c("o","O"))
}

xo <- function(s){
  v = unlist(strsplit(s,""))
  length(v[v=="x"|v=="X"]) == length(v[v=="o"|v=="O"])
}