Classify the following tweet into two categories 'sad' and 'happy'.
I passed my final exam!
The category for the tweet "I passed my final exam!" is 'happy'.
Complete the following task based on the instruction and optional input provided.### Instruction:
Classify the following tweet into two categories 'sad' and 'happy'.

### Input:
I passed my final exam!

### Output:
The category for the tweet "I passed my final exam!" is 'happy'.