n,m = gets.split.map(&:to_i)
s = gets.chomp.split("")
i = 0
j = 1
loop do
  if s[i] == "(" && s[j] == ")"
    s[i] = ""
    s[j] = ""
    if i+1 == m || j+1 == m
      if i+1 == m
        p j+1
      else
        p i+1
      end
      break
    end
    i = 0
    j = 1
  elsif s[i] == "(" && s[j] == "("
    if s[j-1] == ""
      i = j
      j += 1
    else
      i += 1
      j += 1
    end
  elsif s[i] == "(" && s[j] == ""
    j += 1
  elsif s[i] == ""
    i += 1
    j += 1
  end
  i = 0 if i == n-1
  j = 1 if j == n-1
end