displayName provides a pretty print view of the name. It uses data as a value receiver.

printFeature gets the feature for the given point.

setAge sets the age and displays the value. It uses data as a pointer receiver.

valid validates the authorization.

Advanced Encryption Standard https://zh.wikipedia.org/wiki/%E9%AB%98%E7%BA%A7%E5%8A%A0%E5%AF%86%E6%A0%87%E5%87%86

variables , shard type

Breadth-first search

for loop, exit when i >3

exit for range loop by close channel

exit for while loop by ctx.Done

receive only channel 不能 close，直接编译错误。但 send only channel 是可以被正常 close 的

send to a close channel, then panic

receive a close channel, then default value

error to Status Convert is a convenience function which removes the need to handle the boolean return value from FromError.

Depopulate to map

ECB, Electronic codebook

EXPECT returns an object that allows the caller to indicate expected use

Error returns an error representing c and msg. If c is OK, returns nil.

删除root， 删除前先与last交换，最后删除lastItem, 因为root变了， 所有需要MaxHeapifyDown

删除root， 删除前先与last交换，最后删除lastItem, 因为root变了， 所有需要MaxHeapifyDown

Fetch fetches data