func main() {//创建 mapstudens := map[string]string{"name": "张三","age":  "18","sex":  "男",} //直接创建有值的map var m2 map[string]int  //map == nilm3 := make(map[string]string) //map == empty map
}

//获取key元素name := studens["name"]fmt.Println(name) //"张三"

//获取不存在元素idCard := studens["idCard"]fmt.Println(idCard) //打印空 ""所以我们怎么判断,key是否取到了呢?

idCard,ok := studens["idCard"] //其实 获取map可以返回两个参数,第二个就是bool类型,false表示不存在fmt.Println(idCard,ok) // 打印 "" falseif idCard,ok := studens["idCard"];ok {fmt.Println(idCard)}else {fmt.Println("key idCard not exist")}// key idCard not exist

//遍历 mapfmt.Println("----------key value一起遍历------n")//key value一起遍历for k, v := range studens {fmt.Println(k,v)}fmt.Println("---------只遍历key-------n")//只遍历keyfor k := range studens {fmt.Println(k)}fmt.Println("---------只遍历 value-------n")//只遍历 valuefor _, v := range studens {fmt.Println(v)}

//删除存在的键delete(studens, "age")fmt.Println("delete age after:",studens) //delete age after: map[sex:男 name:张三]//删除不存的键delete(studens,"idCard")fmt.Println("delete ont exist key after:",studens) //delete ont exist key after: map[name:张三 sex:男]

"asdjkh" -> "asdjkh" 6个字符
"aaaa"   -> "a"      1个字符
"abccba" -> "abc"    3个字符

package mainimport "fmt"/**
查找到一个字符串中
最长不重复字符串例如：
asdasdss -> asd
*/func findMaxNoRepeatString(s string) int {start := 0keysIndex := make(map[byte]int)lenth := 0for i, v := range []byte(s) {   //这里将字符串转为 byte数组的原因,string遍历每一个元素是int32类型lastIndex, ok := keysIndex[v]if ok && lastIndex >= start {start = lastIndex + 1} else {lenth = i - start + 1}keysIndex[v] = i}return lenth}func main() {fmt.Println(findMaxNoRepeatString("abc"))       //3fmt.Println(findMaxNoRepeatString("abccba"))    //3fmt.Println(findMaxNoRepeatString("aaaaa"))     //1fmt.Println(findMaxNoRepeatString(""))          //0fmt.Println(findMaxNoRepeatString("asdfghjk"))  //8
}

fmt.Println(findMaxNoRepeatString("我是小智"))  //8fmt.Println(findMaxNoRepeatString("小智智小"))  //6