Chapter 4 - Section Hashmaps - need to specify type for first example

[glafrance]

In Chapter 4 - Section hashmaps, for the first example I get an error that you must specify a type annotation for the hashmap.

So instead of this:

let mut scores = HashMap::new();

I did this:

let mut scores: HashMap<_, _> = HashMap::new();

Of course the actual type annotation would depend on the intent of the scores hashmap.