16-01：JS 深度拷贝一个元素的具体实现

var deepCopy = function(obj) { 
  if (typeof obj !== 'object') 
  return; 
  var newObj = obj instanceof Array ? [] : {}; 
  for (var key in obj) { 
    if (obj.hasOwnProperty(key)) {
      newObj[key] = typeof obj[key] === 'object' ? deepCopy(obj[key]) : 
      obj[key]; 
    }
  }
return newObj; 
}