Kotlin常用内置数据类型
| 类型 | 描述 | 示例 |
| String | 字符串 | "Hello,World" |
| Char | 单字符 | 'A' |
| Boolean | true/false | true false |
| Int | 整数 | 5 |
| Double | 小数 | 3.14 |
| List | 元素集合 | "Jack","Rose","Jack" |
| Set | 无重复元素的集合 | "Jack","Jason","Jacky" |
| Map | 键值对集合 | "small" to 5,"medium" to 8,"large" to 9 |
| 类型 | 描述 | 示例 |
| String | 字符串 | "Hello,World" |
| Char | 单字符 | 'A' |
| Boolean | true/false | true false |
| Int | 整数 | 5 |
| Double | 小数 | 3.14 |
| List | 元素集合 | "Jack","Rose","Jack" |
| Set | 无重复元素的集合 | "Jack","Jason","Jacky" |
| Map | 键值对集合 | "small" to 5,"medium" to 8,"large" to 9 |