Tests given on the sheet:
xqzx 
xqdxyyyy
xyyyqqq

// test z and d for wahtzits. 
xqdx  
xqzx  

// test k >= 1 rule on whatzits  for blurbs
x     not a blurb (k=0)
xy    not a blurb
xqd   not blurb (whatzits must end in whoozit)
xqz   not a blurb (whatzits must end in whoozit)

// test multiple whatzits for a blurbu
xqdxqdx
xqdxqdxqdx
xqzxqzxqzxqzx
xqdxqdxqdxqdxqdx

// test multiple y's for whoozits.
xyqdx
xyyqdx
xyyyqdx
xyyyyqdx
xqdxy
xqdxyy
xqdxyyy
xyqdxyy
xyyyqdxyyy

xqdxqz // not a blurb, whatzit doesn't end in a whoozit.
xqdxqdxqd // not a blurb, whatzit doesn't end in a whoozit.

// some random concatenations of q's, x's d's, z's and y's; not blurbs
xxqxdy
xqyxdx
xyyxqdxy
xyxyyxqqddxz
zyxyyqxz

//russell's original tests, reordered so blurbs are in front.
xyyyqzx
xqdxyyyyyyyy
xqdx
xyyyyyyqzxyyyyyyy

xqzxyyyyyyxqzxyyyyyyyyxqzxyxqzxyxyqzxyxyqzxy
qdxyyyyqd
xyyyyyyyqdxxqzxyyyyqzxyy
yyyqzyyyyxqzx
qdqzqdqzxyyy
qd
qz
xx
xyxy
dzxyyyqd