I am hoping the place that sold you these frogs also provided you with a food source.

You should begin culturing fruit flies immediately and obtain the calcium and vitamin supplements you will need to help them survive.
Here is a link to a great article on culturing fruit flies by John and Paul. Frog Forum - Fruit Fly Culturing, Care and Feeding - Everything you need to know about Drosophila

Ask questions and put them in a home with the right environment and conditions.