In a spreadsheet in Google Spreadsheets, I have multiple-choice answers I would like to grade. One row (user 0) contains the answer key, and the other rows contain user answers.

```
User Q1 Q2 Q3 Q4 Q5 Score
0 A C D C B
1 A C B C B [need formula here]
2 B A C D B [need formula here]
```

I'm trying to come up with a spreadsheet formula that would allow me to automatically calculate how many answers for a given user match up with the answer key, but I haven't had much luck.

Any suggestions?