Let's call the last letter L4. Given no prior infomation, the probability of L4 == X, for each value of X in the alphabet, gives you a histogram - which is alwa

Let's call the last letter L4. Given no prior infomation, the probability of L4 == X, for each value of X in the alphabet, gives you a histogram - which is always the same, and can be calculated by looking at the game's dictionary wordlist. If I give you the new information "I guessed L4 on my first guess", you can use this to update the histogram. The more-probable entries in the histogram are now even more probable, and the less-probable entries less probable. For the specific numbers, have a look at Bayesian Inference https://en.wikipedia.org/wiki/Bayesian_inference https://en.wikipedia.org/wiki/Bayesian_inference