package main

import "fmt"

func add(a int, arg ...int) int {
    var sum int = a
    for i := 0; i < len(arg); i++ {
        sum += arg[i]
    }
    return sum
}

func concat(a string, arg ...string) (result string) {
    result = a
    for i := 0; i < len(arg); i++ {
        result += arg[i]
    }
    return
}

func main() {
    sum := add(1, 2, 3, 4, 5)
    fmt.Println(sum)

    result := concat("a", "b", "c", "d", "e")
    fmt.Println(result)
}

package main

import "fmt"

func main() {
    var i int = 0
    defer fmt.Println(i)
    defer fmt.Println(1)
    i = 10
    fmt.Println(i)
}

/*输出：
10
1
0
*/

package main

import "fmt"

func main() {
    result := func(a int, b int) int {
        return a + b
    }
    fmt.Println(result(1, 2))
}