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kirkulator
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I am studying Integer Modulo in my Cryptography and Data Security class. We are dealing with mainly modulo 26 [the alphabet] right now. I understand if it is addition or multiplication you just take the remainder of the result divided by, let's say 26 in this circumstance. ie: (5+25)mod26 = 4
ie: (5*6)mod26 = 4
But I'm not quite understanding how to do mod26 when there results a negative number.
ie: the shift cipher is (x-k)mod26
which usually results in a negative because k is usually > x
so say, if i had -7mod26
how would i go about this?
Also is there any way to calculate this sort of problem on my calculator to check my work? I have a TI-83.
Thanks so much guys.
Amanda
ie: (5*6)mod26 = 4
But I'm not quite understanding how to do mod26 when there results a negative number.
ie: the shift cipher is (x-k)mod26
which usually results in a negative because k is usually > x
so say, if i had -7mod26
how would i go about this?
Also is there any way to calculate this sort of problem on my calculator to check my work? I have a TI-83.
Thanks so much guys.
Amanda