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# converting some simple pseudocode to c++

Joah Senegal
Guest
Posts: n/a

 12-17-2007
Hello all,

I;m a beginner C++ and I;m trying to convert some pseudocode into C++. Its
pseudo code of the peterson algorithm for N-processes.

I almost converted the whole code. But the last lines are very hard.

This is the pseudo code:

for [ k=1 to n except k==i ]

This is pretty simple code although I don;t know how to convert in into c++
because of the except in the pseudocode. for [k=1 to n] to c++ is for
(k=1;k<n;k++). i dont understand it because of the except.

Is there anyone who can tell me what the C++ code is for the above pseudo
code?

I;ve another little bit more complex part of pseudocode as well

wait until ((for all k<>i q[k]<j) or (turn[j]<>i)).

Is there anyone who can give me the c-code for one of this pseudo codes ? I
would be very gratefull if anyone can translate one of the pseudocodes. this
one is the most important

for [ k=1 to n except k==i ]

many many thanks!!!!

Lance Diduck
Guest
Posts: n/a

 12-17-2007
On Dec 17, 10:04 am, "Joah Senegal" <(E-Mail Removed)> wrote:
> Hello all,
>
> I;m a beginner C++ and I;m trying to convert some pseudocode into C++. Its
> pseudo code of the peterson algorithm for N-processes.
>
> I almost converted the whole code. But the last lines are very hard.
>
> This is the pseudo code:
>
> for [ k=1 to n except k==i ]
>
> This is pretty simple code although I don;t know how to convert in into c++
> because of the except in the pseudocode. for [k=1 to n] to c++ is for
> (k=1;k<n;k++). i dont understand it because of the except.
>
> Is there anyone who can tell me what the C++ code is for the above pseudo
> code?
>
> I;ve another little bit more complex part of pseudocode as well
>
> wait until ((for all k<>i q[k]<j) or (turn[j]<>i)).
>
> Is there anyone who can give me the c-code for one of this pseudo codes ? I
> would be very gratefull if anyone can translate one of the pseudocodes. this
> one is the most important
>
> for [ k=1 to n except k==i ]
>
> many many thanks!!!!

for(int k=1,k!=n;++k){
if(k==i)continue;
//do stuff
}

Victor Bazarov
Guest
Posts: n/a

 12-17-2007
Joah Senegal wrote:
> I;m a beginner C++ and I;m trying to convert some pseudocode into
> C++. Its pseudo code of the peterson algorithm for N-processes.
>
> I almost converted the whole code. But the last lines are very hard.
>
> This is the pseudo code:
>
> for [ k=1 to n except k==i ]
>
> This is pretty simple code although I don;t know how to convert in
> into c++ because of the except in the pseudocode. for [k=1 to n] to
> c++ is for (k=1;k<n;k++).

Note that in Lance's answer the condition for the loop is k<=n, not
k<n like you gave here.

> i dont understand it because of the except.
>
> Is there anyone who can tell me what the C++ code is for the above
> pseudo code?
>
> I;ve another little bit more complex part of pseudocode as well
>
> wait until ((for all k<>i q[k]<j) or (turn[j]<>i)).
>

Since C++ does not have "wait" equivalent, you might want to give
more context to see if the translation is possible. Of course,
most likely, due to 'for all' a single-line translation isn't what
you'd naturally come up with. 'for all' needs a loop. Even if
you manage to utilise standard function like 'for_each' or some
such, you would still most likely need a functor, which will be
written as a separate class. For now this is what it looks like
to me:

wait_here:
// wait somehow

bool all_q_are_less_than_j = true;
for (int k = start_k; k <= end_k; ++k) { // start_k, end_k???
if (k != i && !(q[k] < j)) {
all_q_are_less_than_j = false;
break;
}
}
if (all_q_are_less_than_j || turn[j] != i)
// do something, like move forward or whatever...
else
goto wait_here;

V
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