Welcome to CS 106B Word Ladder.
Please give me two English words, and I will change the
first into the second by changing one letter at a time.

Dictionary file name? notfound.txt
Unable to open that file.  Try again.
Dictionary file name? oops.txt
Unable to open that file.  Try again.
Dictionary file name? smalldict1.txt

Word #1 (or Enter to quit): code
Word #2 (or Enter to quit): data
A ladder from data back to code:
data date cate cade code 

Word #1 (or Enter to quit): ghost
Word #2 (or Enter to quit): boo
The two words must be the same length.

Word #1 (or Enter to quit): marty
Word #2 (or Enter to quit): keith
The two words must be found in the dictionary.

Word #1 (or Enter to quit): kitty
Word #2 (or Enter to quit): kitty
The two words must be different.

Word #1 (or Enter to quit): dog
Word #2 (or Enter to quit): cat
A ladder from cat back to dog:
cat cot cog dog 

Word #1 (or Enter to quit):
Have a nice day.