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Hi, I don't know about in the US but in AUS we have 10 digit moblile numbers. Given that each number has 3 possible letters you might use in round numbers the search space is 59049 letter combinations per number

Unfortunately the generation of the test keys is not *particularly* straight forward. Using my ten digit scenario for each of the 59049 test cases we might have:

one word (a) where a=10 letters

two words (a,b) where a+b=10 letters,

three words (a,b,c) where a+b+c = 10 letters

.....

ten words (a..j) where a+b+c+d+e+f+g+h+i+j=10 letters If you remember the binomial expansion (as I vaguely do - it was a while ago) you will remember the pyramid:

1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 1 7 21 35 35 21 7 1 1 8 28 56 70 56 28 8 1 1 9 36 84 126 126 84 36 9 1

What this shows us is that while there is obviously only one test case for a ten letter match there are 9 possibilities for an a+b=10 letter match, 36 possibilities for an a+b+c=10 letter match....

Adding this up we find that there are 512 possibilities we need to consider for each of the 59049 10 letter combinations. The total search space is 30,233,088. I thought this might take a long time but that was when I thought it would be a somewhat larger search space. Should be doable in under a minute of CPU time.

more to follow...

tachyon

In reply to Re: (Golf) mobile phone numbers - words by tachyon
in thread (Golf) mobile phone numbers -&gt; words by mischief

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