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Update "a**b" writting to "a^b" in diffie-hellman description #1933

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Merged
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Jan 29, 2022
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Update "a**b" writting to "a^b" in diffie-hellman description #1933

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Update "a**b" writting to "a^b" in diffie-hellman description
Gautzilla Jan 28, 2022
90617be
Delete .vs additional directory
Gautzilla Jan 28, 2022
30f4900
Update a^b notation to aᵇ notation.
Gautzilla Jan 29, 2022
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6 changes: 3 additions & 3 deletions exercises/diffie-hellman/description.md
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Expand Up @@ -19,7 +19,7 @@ the same to pick a private key b.

Alice calculates a public key A.

A = g**a mod p
A = gᵃ mod p

Using the same p and g, Bob similarly calculates a public key B from his
private key b.
Expand All @@ -28,11 +28,11 @@ private key b.

Alice and Bob exchange public keys. Alice calculates secret key s.

s = B**a mod p
s = Bᵃ mod p

Bob calculates

s = A**b mod p
s = Aᵇ mod p

The calculations produce the same result! Alice and Bob now share
secret s.
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I would like to suggest adding a note be added at the end of this document that mentions that in some programming languages ** is used as the method to indicate exponentiations instead of ^.

I think just replacing one form for another doesn't necessarily clear up the confusion for everyone, just shifts it.

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@wolf99 wolf99 Jan 28, 2022 •
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Might it be better to remove any implementation dependent form and instead use the mathematical form? (i.e. aᵇ).
That is what is being described after all.

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Hard agree with @wolf99 comment. For example, in Python, ^ is used as a set operator, which is why ** is used for exponentiation. It varies widely by programming language.

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@wolf99 I like your suggestion, however I worry about how the special character will translate for users. If there is no concern to worry about then 👍 from me too.

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@Gautzilla Gautzilla Jan 29, 2022 •
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I feel exactly like @rpottsoh : would aᵇ render properly in any IDE for people downloading the exercise through CLI?

I would like to suggest adding a note be added at the end of this document that mentions that in some programming languages ** is used as the method to indicate exponentiations instead of ^.

The note might just mention that a^b means "a raised to the power of b", or "aaa*...*a" b times", so that the description only uses mathematics and no programming conventions?

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@SaschaMann SaschaMann Jan 29, 2022 •
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We have other exercises that use them. If an IDE can't display standard characters like that, it's most likely a deliberate choice by the student to use an archaic IDE and make their life hard.

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Thus, I see no reason not to use this notation. I'll make a new commit.

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deliberate choice by the student to use archaic IDE

I use ed (not always) and it displays it, so I wonder if you mean "IDE that sucks" rather than archaic.

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Instead of trying to abstract it away:

s = (A to the power of b) mod p