> For the complete documentation index, see [llms.txt](https://gold.gitbook.io/kotlin/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gold.gitbook.io/kotlin/collections/untitled.md).

# Mutable

```kotlin
val mutableList: MutableList<Int> = mutableListOf(1,2,3,4,5)

mutableList.add(6)

for (i in 0 until mutableList.size) {
    println(mutableList.get(i)) // 1,2,3,4,5,6
}
```