import sequtils, strutils

let
  nk = stdin.readLine.split.map parseInt
  n = nk[0]
  k = nk[1]
  s = readLine stdin
var
  a = (1..n).toSeq
  b = s
  c = (-1).repeat n

while b.len > 0:
  let
    i = b.find "()"
    j = i.succ
  
  c[a[i].pred] = a[j]
  c[a[j].pred] = a[i]
  a.delete i..j
  b.delete i, j

echo c[k.pred]