Classify the following tweet as sarcastic, non-sarcastic, or non-determinable.
This is the best day ever!
Non-determinable.
Complete the following task based on the instruction and optional input provided.### Instruction:
Classify the following tweet as sarcastic, non-sarcastic, or non-determinable.

### Input:
This is the best day ever!

### Output:
Non-determinable.