freqs("time flies like an arrow, fruit flies like a bananna.");
In the above phrase, there are 9 spaces, 6 each of the letters ``i'' and ``a'', ``e'' appears 5 times, and so on. [Hint: I found it useful to group identical letters in the text using Implode(sort(Explode(text)) , but you might not.]
fmw segjaweoouanerj a ceyqrype aswaheoaqbrqabeafrua eeaojerf afmjeayperjpu
Hint: this phrase follows the the typical pattern in English where there are as many spaces as words (so spaces are very common), and the letter ``e'' is also very common. You can use the technique described in chapter 4 of the notes, section 7.3.
Hint: the above used an affine matrix cipher on 2-vectors, with the 67-letter alphabet
You should be able to guess what the first 20 letters of the message are.