分享出来几个go面试题,都非常简单,如果您有一些开发时候使用到的小技巧欢迎评论。
目前我写出来11个(再更新一道题目),未来会不定期更新。。。
package main import ( "fmt" ) func main() { defer_call() } func defer_call() { defer func() { fmt.Println("打印前") }() defer func() { fmt.Println("打印中") }() defer func() { fmt.Println("打印后") }() panic("触发异常") }
2、 以下代码有什么问题,说明原因
type student struct {Name stringAge int}func pase_student() {m := make(map[string]*student)stus := []student{{Name: "zhou", Age: 24},{Name: "li", Age: 23},{Name: "wang", Age: 22},}for _, stu := range stus {m[stu.Name] = &stu}}
3、下面的代码会输出什么,并说明原因
func main() {
runtime .GOMAXPROCS(1)
wg := sync.WaitGroup{}
wg.Add(20)
for i := 0; i < 10; i++ {
go func() {
fmt.Println("i: ", i)
wg.Done()
}()
}
for i := 0; i < 10; i++ {
go func(i int) {
fmt.Println("i: ", i)
wg.Done()
}(i)
}
wg.Wait()
}
4、下面代码会输出什么?
type People struct{} func (p *People) ShowA() { fmt.Println("showA") p.ShowB() } func (p *People) ShowB() { fmt.Println("showB") } type Teacher struct { People } func (t *Teacher) ShowB() { fmt.Println("teacher showB") } func main() { t := Teacher{} t.ShowA() }
5、下面代码会触发异常吗?请详细说明
func main() {
runtime.GOMAXPROCS(1)
int_chan := make(chan int, 1)
string_chan := make(chan string, 1)
int_chan <- 1
string_chan <- "hello"
select {
case value := <-int_chan:
fmt.Println(value)
case value := <-string_ ch an:
panic(value)
}
}
6、下面代码输出什么?
func calc (index string, a, b int) int {
ret := a + b
fmt.Println(index, a, b, ret)
return ret
}
func main() {
a := 1
b := 2
defer calc("1", a, calc("10", a, b))
a = 0
defer calc("2", a, calc("20", a, b))
b = 1
}
7、请写出以下输入内容
func main() { s := make([]int, 5) s = append(s, 1, 2, 3) fmt.Println(s) }
8、下面的代码有什么问题?
type UserAges struct { ages map[string]int sync.Mutex } func (ua *UserAges) Add(name string, age int) { ua.Lock() defer ua.Unlock() ua.ages[name] = age } func (ua *UserAges) Get(name string) int { if age, ok := ua.ages[name]; ok { return age } return -1 }
9、下面的迭代会有什么问题?
func (set *threadSafeSet) Iter() <-chan interface{} { ch := make(chan interface{}) go func() { set.RLock() for elem := range set.s { ch <- elem } close(ch) set.RUnlock() }() return ch }
10、以下代码能编译过去吗?为什么?
package main import ( "fmt" ) type People interface { Speak(string) string } type Stduent struct{} func (stu *Stduent) Speak(think string) (talk string) { if think == "bitch" { talk = "You are a good boy" } else { talk = "hi" } return } func main() { var peo People = Stduent{} think := "bitch" fmt.Println(peo.Speak(think)) }
11、以下代码打印出来什么内容,说出为什么。。。
package main import ( "fmt" ) type People interface { Show() } type Student struct{} func (stu *Student) Show() { } func live() People { var stu *Student return stu } func main() { if live() == nil { fmt.Println("AAAAAAA") } else { fmt.Println("BBBBBBB") } }
本文来自:知乎专栏
感谢作者:诺唯