# Towers of Hanoi

C

#### Constant

I need a programe that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++

A

#### Alexandros

Constant escribió:
I need a programe that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++

Here you are a program wich solves the problem:

#include <iostream>
using namespace std;

void hanoi (int nDisks, int pegA, int pegB, int pegC)
{
if (n>0) {
hanoi (nDisks - 1, pegA, pegC, pegB);

cout << "Move disk from peg " << pegA << " to peg " << pegC << endl;

hanoi( nDisks-1, pegB, pegA, pegC);
}
}

int main ()
{
int n;
cout << "Input number of disks: ";
cin >> n;

hanoi (n, 1, 2, 3);

return 0;
}

K

#### Karl Heinz Buchegger

Please do not solve other peoples homework.
Give him some hints, try to make him thinking about
the problem, but do not post a program he can turn in
without actually having mastered the problem by himself.

Hanoi is often used to check if a student has grasped
the concept of recursion. He needs to build up a mental
model on how recursion works in order to solve it with
recursion:
a) What makes the problem complicated?
b) What parameter can be made simpler, such that
finally this parameter reaches 0 or 1 or any other
trivial case.
c) What is the trivial case, how can it be solved?
d) How can I use a simpler solution to find the solution
for the more complex problem.

By providing him a complete workable solution,
you have defeated that intention.

Thank you.

PS (for the OP):
a) the number of disks. Obviously, if no disk must be moved
the problem is so simple, that even a 2 year old child can solve
it: do nothing.
b) again, the number of disks. Moving n-1 disks is easier then
moving n disks.
c) Having to move 0 disks. No action is required then.
d) To move n disks from a StartPad to GoalPad with the help
* move n-1 disks from StartPad to ParkingPad, in order to free
the n-th disk for movement. You can use the GoalPad as the parking pad.
* move the n-1 disks you have parked at ParkingPad, from ParkingPad

moving n-1 disks is simpler then moving n disks. Thus the above
uses the solution of simpler problems to solve the problem for n.

M

#### Mike Wahler

Constant said:
I need a programe
This is not a 'program supply' group. It's a group
for discussing the C++ language.
that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++

No C++ knowledge or computer knowledge at all is required
to solve this problem. It can (and imo should) first be
done with paper and pencil. Once you've worked out and
tested (again on paper) your algorithm, only then is is
time to translate it into a programming language.

WHen you have some code representing your best attempt,
but are still stuck or confused, then by all means post it here
and ask specific questions. That's how to get quality assistance
here.

-Mike

G

#### Gavin Deane

I need a programe that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++

Do you know how to solve the problem in English or your native
language? Before you start to write any C++ you'll need to be able to
fully describe the algorithm in natural language. It's not very
complicated but you'll need to be precise. Once you've done that,
start translating it into C++.

Or are you at the coding stage already? If so, post compileable code
that demonstrates your problem. Include compiler messages and/or
program output that you don't understand and explain what you expect
to happen. Then people will be able to help.

Good luck.
GJD

M

#### Mike Wahler

osmium said:
The notion of making some marks on paper for a recursive solution makes me
slightly dizzy.

Then stop spinning around.
I can't imagine what those marks would be

They would be e.g. names and values of variables at
given points of execution.

or what they
would represent.

Data and control flow.
IMO a recursive problem must be held and solved, to some

Some can do that easily, others have trouble.
A *vision*, if you will.

on on top of the other. Each succeeding 'page' would
represent a level of recursion.
The next step: a computer
program or at least pseudocode. Your mileage obviously varies.

Yup.

-Mike

O

#### osmium

Mike said:
No C++ knowledge or computer knowledge at all is required
to solve this problem. It can (and imo should) first be
done with paper and pencil. Once you've worked out and
tested (again on paper) your algorithm, only then is is
time to translate it into a programming language.

The notion of making some marks on paper for a recursive solution makes me
slightly dizzy. I can't imagine what those marks would be or what they
would represent. IMO a recursive problem must be held and solved, to some
degree, in the head. A *vision*, if you will. The next step: a computer
program or at least pseudocode. Your mileage obviously varies.

J

#### Jack Klein

I need a programe that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++

#include <check_calendar>

Yep, still September!

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
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N

#### Noah Roberts

Constant said:
I need a programe that will deal with the solving of the problem ..i
have 3 pegs A, B, C...and I want to move the disk A to disk C using B
as auxiliary.At the end all disk should be at peg C in the same order
as in the beginning.
I do not know how to solve this problem because I have only basic
skill in C++