In this directory, you should write the program `wcat.c` and compile it into
the binary `wcat`.

After doing so, you can run the tests from this directory by running the
`test-wcat.sh` script. If all goes well, you will see:

```sh
prompt> ./test-wcat.sh
test 1: passed
test 2: passed
test 3: passed
test 4: passed
test 5: passed
test 6: passed
test 7: passed
prompt>
```

`test-wcat.sh` is just a wrapper for the `run-tests.sh` script in the `tester`
directory of this repository. This program has a few options; see the relevant
README for details.