package main

import (
	"fmt"
)

const (
	// 可以在const()添加一个关键字iota，每行的iota都会累加1， 第一行的iota默认值是0
	BEIJING = 10 * iota
	SHANGHAI
	SHENZHEN
)

const (
	a, b = iota + 1, iota + 2 // iota = 0, a = 1, b = 2
	c, d                      // iota = 1, c = 2, d = 3
	e, f                      // iota = 2, e = 3, f = 4
	g, h = iota * 2, iota * 3 // iota = 3, g = 3 * 2 = 6, h = 3 * 3 = 9
	i, k                      // iota = 4, i = 4 * 2 = 8, k = 4 * 3 = 12
)

func main() {
	// 常量（只读属性）
	const length int = 10

	fmt.Println("length = ", length)

	fmt.Println("BEIJING = ", BEIJING)
	fmt.Println("SHANGHAI = ", SHANGHAI)
	fmt.Println("SHENZHEN = ", SHENZHEN)

	fmt.Println("a = ", a, "b = ", b)
	fmt.Println("c = ", c, "d = ", d)
	fmt.Println("e = ", e, "f = ", f)
	fmt.Println("g = ", g, "h = ", h)
	fmt.Println("i = ", i, "k = ", k)
}