Can you solve the headlines with your computer?
The puzzle comprises enciphered Headlines. No other information is given. Here is an example:
(1) GJSUJD GDCUUSU DHNPGCE: USEJIS TOSSU PE XJEPG.
(2) BMKKLRK DMK GHMU MUJ DRUNAI GVVQ.
(3) YVWPX FATXL KEVPAPF EIWOQ ABXL WD HEVYC.
(4) VKSFSE TBOKTZTBQFNR TB HTXXNK IXLF
(5) TWJA WHLBHP VWTKHLR WHZ UBJJBIR KWJR.
The first step is to decipher the headlines. Can you do it? If you can’t then read below.
Because the headlines have been enciphered with a simple mono-substitution, one would usually solve by hillclimbing. But the ciphertexts are so short that this will not work. Try it if you like on my hillclimber here.
An alternative way in is to seek a pattern word in one of the headlines and to look at a list of words with that pattern. The drawback is that such a list will usually contain dozens of words and it’s difficult to pick out the correct one. An exception is TBOKTZTBQFNR in headline nr 4 which has just two options: incriminates, incriminated which then allows:
(4) VKSFSE TBOKTZTBQFNR TB HTXXNK IXLF
.r.t.. incriminate. in .i..er ...t
but even with this knowledge there are still myriads of possibilities. However if one considers two words with letters in common there will be limited possibilities for solutions, especially when some of the letters are known. So if we consider: HTXXNK and IXLF which have cipher X in common, and knowing that TBOKZQFNR = incrmnate, then if we try every possible word for HTXXNK and see which words are possible for IXLF, we find just one pair: ‘-iller’ and ‘plot’. The first word could be biller, filler, killer. Only ‘killer’ makes sense. Again using word lists, the first word must be ‘brutus’ and we’ve solved the headline.
Of course there’s been an awful lot of list making, and trial and error, to get the solution and for a human this is all rather tedious. But for the computer it’s easy and can be done in a flash. To see this in action, go here and put each headline into the solver.
Even better write your own solving program using the word sieving algorithm, which you can read about here.
The solved Headlines are:
GJSUJD GDCUUSU DHNPGCE: USEJIS TOSSU PE XJEPG.
caesar crosses rubicon: senate flees in panic.
BMKKLRK DMK GHMU MUJ DRUNAI GVVQ.
cassius has lean and hungry look.
YVWPX FATXL KEVPAPF EIWOQ ABXL WD HEVYC.
crone gives warning about ides of march.
VKSFSE TBOKTZTBQFNR TB HTXXNK IXLF
brutus incriminated in killer plot
TWJA WHLBHP VWTKHLR WHZ UBJJBIR KWJR.
mark antony laments and borrows ears.