Anjali and Tasty Treat

Anjali loves food and she loves to cook. With time, she has mastered the art of transforming a cooked dish into another one. A dish can be represented as a string, where the ingredients are denoted by upper case English alphabets, and the order of ingredients does matter. She has already cooked a dish $A$ which she wants to transform to another dish $B$. There are three types operations which she