import UIKit

var str = "Hello"

var newString = str + "Lucy"

var newTypeString = NSString(string: newString)

newTypeString.substringFromIndex(5)

newTypeString.substringToIndex(5)

newTypeString.substringWithRange(NSRange(location: 3,length: 5))

if newTypeString.containsString("Lucy"){
  print("Hi")
}

newTypeString.componentsSeparatedByString("o")

newTypeString.uppercaseString

newTypeString.lowercaseString