PHP code writing

I need a few lines of php code written for an e-commerce product description page..

Currently I am using this bit of code which displays the stock level

CURRENT STOCK:

It displays it like this

CURRENT STOCK: 7


I would like 2 if rules added to it

1. If the stock level is "0" then it displays: - (a dash or hyphen)

2. If the stock level is greater than "10" then it displays: +10

Thanks

Matt