How to do my best without any distractions.

Before you go to sleep, make some basic decisions about what you will do tomorrow, such as what you will wear, what you will eat for lunch, and the route you will take to work. It is easier to pack a healthy lunch the night before than to decide what you are going to have with a hot dog vendor parked in front of your workplace.

The same applies when it comes to spending money. Decide on a budget and stick to it.

to answer your question:

f(x)= a^x.  if x=0, f(x)=1  if x=1, f(x)=a  if x=1, f(x)=a^a