Write a program in a language of your choice to read in two CSVs with the same columns as those below, inner join them on `userid`, and return the joined rows. Instead of two separate `min_score` columns, combine them in a single `min_score` column filled with the min of the `min_scores` from each input CSV.
Example:
```
input1.csv
userid,age,min_score
1,23,6
6,54,300
2,39,40
input2.csv
userid,state,min_score
1,CA,12
6,AK,44
2,WA,100
output.csv
userid,age,state,min_score
1,23,CA,6
6,54,AK,44
2,39,WA,40
```