package main

import "fmt"

//包内的变量
var aa = 2

var ( bb = 20 cc = true ss = "sss"
)
func variable()  { //变量定义，使用关键字 var a int var s string //fmt.Println(a,s) //%q会把引号带出来 fmt.Println("variable") fmt.Printf("%d %q\n",a,s)
}

func initValue()  { //变量的初始化 var a int=3 var c,d int=3 ,4 var s string = "abc" fmt.Println("initValue") fmt.Println(a,s) fmt.Println(c,d) fmt.Println(aa,bb,cc,ss)
}

func deductionType()  { //类型推断 var a,b,c,d=3,4,true,"def" fmt.Println("deductionType") fmt.Println(a,b,c,d) //简写冒号赋值 e,f,g,h := 3,4,true,"def" fmt.Println(e,f,g,h)
}

func main()  { fmt.Println("hello word") variable() initValue() deductionType()
}

const filename = "abc.txt"
const a, b = 3,4 
const (
  d, e = 5,6 
)

 const( //iota表示const是自增值的 cpp = iota //_表示跳过一个数 _ java php )
  fmt.Println(cpp)
  // 运算 const( b = 1 << (10 * iota) kb mb gb tb pb )

var c int = int(math.Sqrt(float64(3*3+4*4)))

var a int = 2
var pa * int = &a 
* pa = 3
fmt.Println(a)