package mainfunc main()  {r2 := power1(2,4)println(r2)
}
func power1(a uint64, b uint64) (r uint64) {         //a是底数，b是幂，返回rvar i uint64var temp uint64if a != 0{temp = 1for i=1;i<=b;i++{temp = temp * a}return temp}return //这里return只是占一个位置，不然会报错，实际不返回任何值；并且这个函数在调用时候，只能接收一个值，否则会报错
}

package mainfunc main()  {t1, t2 := test(10,20)println(t1)println(t2)
}func test(a int, b int)(r1 int, r2 int)  {return a + b, a - b
}

package mainimport "fmt"func main() {fmt.Println("test\n")    //换行符fmt.Println("test\\n")   //使用转义字符，打印\n；fmt.Println("test\rttt") //遇到\r的时候，换行打印后面内容fmt.Println("test\ttt")  //空一格tab键的长度，打印后面内容fmt.Println("test\vtt")  //空格长度是\t的一半
}

C:/Users/Adong/Adong.exe  [C:/Users/Adong]
testtest\n
test
ttt
test    tt
test tt

package mainimport "fmt"func main() {const a int = 0const b string = "hello!!!"a = 2   //如果编译的话，这个地方会出错，因为给常量重新赋值了fmt.Println(a)fmt.Println(b)
}

C:/Go/bin/go.exe build -i [C:/Users/Adong]

# _/C_/Users/Adong

.\test.go:8:4: cannot assign to a

错误: 进程退出代码 2.

package mainimport "fmt"func main() {const a int = 0const b string = "hello!!!"var c uintc = 1c = 2     //变量可以重新赋值，以最新的赋值为准//a = 2   //如果编译的话，这个地方会出错，因为给常量重新赋值了fmt.Println(a)fmt.Println(b)fmt.Println(c)
}

package mainimport "fmt"func main() {const (a = 0b = 1c = 2)fmt.Println(a)fmt.Println(b)fmt.Println(c)
}

C:/Go/bin/go.exe build -i [C:/Users/Adong]

成功: 进程退出代码 0.

C:/Users/Adong/Adong.exe [C:/Users/Adong]

0

1

2

成功: 进程退出代码 0.

package mainimport "fmt"func main() {const (a = 0b = 1c = 2d)fmt.Println(a, b, c, d)
}

// 执行结果：0 1 2 2

package mainimport "fmt"func main() {const (i = iota //0a        //1b = "heh"c = "heh"d = iotae)fmt.Println(a, b, c, d, e)
}

package mainimport "fmt"func main() {const (i = iota //0a        //1b = "heh"c = "heh"d = iotae)fmt.Println(a, b, c, d, e)
}

//执行结果：1 heh heh 4 5