Create a script for magento to copy products from one category to another

Hi everyone, I am looking for a magento expert who can help me with the following: 1) I have some product categories in my store with products assigned to them, but when I create a new category sometimes I need to copy the same products of one category to the new category. I need a script for this purpose. So the exact products of category X will also be assigned to the new category y 2) The script must also be able to assign products to a category by simply entering a list of product id's or sku's. I am using magento version: 1.9.2.1 Looking forward hearing from you.