language: python prompt: https://adventofcode.com/2020/day/6

```
#!/usr/bin/env python3
from functools import reduce
groups = open('./input').read().split('\n\n');
def count_using(f, groups):
def count(s):
sets = map(set, s.split('\n'))
elems = reduce(f, sets)
return len(elems)
return sum(map(count, groups))
def main():
union = lambda a,b: a.union(b)
print('Total (uniq answers):', count_using(union, groups))
intersection = lambda a,b: a.intersection(b)
print('Total (same answers):', count_using(intersection, groups))
main()
```