Inventory

Build an inventory tracker! Start with an empty HashMap, then:

1. Add "apples" with quantity 5
2. Add "bananas" with quantity 3
3. Add "oranges" with quantity 7
4. Update "apples" to quantity 10 (just insert again with the new value)

Print each item and its quantity in alphabetical order.

Expected output:

apples: 10
bananas: 3
oranges: 7

Hints:

• Start with let mut inventory = HashMap::new();
• Use .insert() to add items -- inserting the same key again updates the value
• Collect keys, sort, and loop to print in order