import "fmt"

//聲明一個新的類型
type person struct {
 name string
 avg  int
}

//比較兩個人的年齡，返回年齡大的那個人，并且返回年齡差
//struct 也是傳值的
func older(p1, p2 person) (person, int) {
 if p1.avg > p2.avg { //比較p1和p2年齡
  return p1, p1.avg - p2.avg
 }
 return p2, p2.avg - p1.avg
}

func main() {
 var tom person
 //賦值初始化
 tom.name, tom.avg = "Tom", 18

 //兩個字段都寫清楚的初始化
 bob := person{avg: 25, name: "Bob"}

 //按照struct定義順序初始化
 paul := person{"Paul", 43}

 tb_Older, tb_diff := older(tom, bob)
 tp_Older, tp_diff := older(tom, paul)
 bp_Older, bp_diff := older(bob, paul)

 fmt.Printf("Of %s and %s, %s is older by %d years\n",
  tom.name, bob.name, tb_Older.name, tb_diff)
 fmt.Printf("Of %s and %s, %s is older by %d years\n",
  tom.name, paul.name, tp_Older.name, tp_diff)
 fmt.Printf("Of %s and %s, %s is older by %d years\n",
  bob.name, paul.name, bp_Older.name, bp_diff)
}

import (
 "fmt"
)

type Human struct {
 name   string
 age    int
 weight int
}
type Student struct {
 Human      //匿名字段，那么默認(rèn)struct就包含了Human所有字段
 speciality string
}

func main() {
 //初始化一個學(xué)生
 mark := Student{Human{"Mark", 25, 100}, "Computer Science"}

 //訪問相應(yīng)的字段
 fmt.Println("His name is ", mark.name)
 fmt.Println("His age is ", mark.age)
 fmt.Println("His weight is ", mark.weight)
 fmt.Println("His speciality is ", mark.speciality)

 //修改對應(yīng)的信息
 mark.speciality = "AI"
 fmt.Println("Mark changed his speciality")
 fmt.Println("His speciality is ", mark.speciality)
 //  修改他的年齡信息
 fmt.Println("Mark become old")
 mark.age = 46
 fmt.Println("His age is", mark.age)
 //  修改他的體重信息
 fmt.Println("Mark is not an athlet anymore")
 mark.weight += 60
 fmt.Println("His weight is", mark.weight)
}