# Problem Set 4

## What to Do

1. Submit one of:
2. Submit Recover

If you submit both versions of Filter, we’ll record the higher of your two scores.

## When to Do It

By .

• If you see any errors when compiling your code with make, focus first on fixing the very first error you see, scrolling up as needed. If unsure what it means, try asking help50 for help. For instance, if trying to compile hello, and
make filter

help50 make filter