How would I reverse engineer a cryptographic algorithm?

Question

I wrote an application that encrypts text in this way:

1. Get the input text

2. Reverse the text

3. Convert to hexadecimal

4. <

Answer 1

Ciphertext indistinguishability is a good page to start with to understand what crypto algorithms are designed to prevent/defend against. The type of attacks (e.g. IND-CPA) mentioned can also give you a clue about what you can start with.