You will need to have Go installed to compile from source code. Once you have Go installed, you can:
go build
and then
./cmsc412-hw1
It will try to read in graph.txt from the present working directory and output wdegree.txt in the same directory.
Here is the link to download Go https://golang.org/doc/install
If you don't feel like downloading, installing, and configuring Go, I've compiled it for the major operating systems and I have them availble for download on my website.
You may need to sudo chmod 500 cmsc412-hw1 to get execute permissions