gistfile1.txt

import Foundation



var checkOpenCloseBracket:((String, String) -> Bool)!
checkOpenCloseBracket = { (openBracket, closeBracket) in
  var result: Bool
  switch (openBracket, closeBracket) {
  case _ where openBracket == "{" && closeBracket == "}":
    result = true
  case _ where openBracket == "[" && closeBracket == "]":
    result = true
  case _ where openBracket == "(" && closeBracket == ")":
    result = true
  default:
    result = false
  }
  return result
}

func checkBracket(var brackets: String) {
  var list: [String] = []
  
  tokenLoop: for (index, bracket) in enumerate(brackets) {
    switch String(bracket) {
    case let token where (token == "{") || (token == "[") || (token == "("):
      list += [token]
    case let token where (token == "}") || (token == "]") || (token == ")"):
      let openBracket = list.removeLast()
      let result = checkOpenCloseBracket(openBracket, token)
      if !result {
        println("Error, index : \(index)")
        break tokenLoop
      }
    default:
      break
    }
  }
  
  if !list.isEmpty {
    println("Error!, \(list)")
  }
}

checkBracket("[]{}()")
checkBracket("[]{()}")
checkBracket("[]{(}}")
checkBracket("[]{{{{{{{{{{{}}}}}}")