fun char read_char(int i) = read(char)

fun [char] read_string(int n) = map(read_char, iota(n))

fun int add_one(int x) = x + 1

fun [char] main() =
  let n = read(int) in
  let s1 = read_string(n) in
  let s2 = map(chr, map(add_one, map(ord, s1))) in
  write(s2)
