public/subjects/listsizeprog.en.md

## listsizeprog

### Instructions

Write a function `ListSize` that returns the number of elements in a linked list `l`.

### Expected function and structure

```go
type NodeL struct {
	Data interface{}
	Next *NodeL
}

type List struct {
	Head *NodeL
	Tail *NodeL
}

func ListSize(l *List) int {

}
```