하노이의 탑

1. 개요

2. 설명

3. 프로그래밍

3.1. OCaml

let rec move_tower n a b c = match n with
	| 1 -> [(a,c)]
	| _ -> (move_tower (n-1) a c b) @ (move_tower 1 a b c) @ (move_tower (n-1) b a c);;

3.2. LISP

#!syntax lisp
(defun hanoitowers (disc src aux dst)
  (cond ((> disc 0)
	 (hanoitowers (- disc 1) src dst aux)
	 (princ (list "Move" disc "from" src "to" dst))
	 (hanoitowers (- disc 1) aux src dst))))

3.3. Pascal

procedure Hanoi(n: integer; from, dest, by: char);
Begin
    if (n=1) then
        writeln('Move the plate from ', from, ' to ', dest)
    else begin
        Hanoi(n-1, from, by, dest);
        Hanoi(1, from, dest, by);
        Hanoi(n-1, by, dest, from);
    end;
End;

3.4. C

#!syntax cpp
#include <stdio.h>

void HanoiTower(int numOfDisks, char from, char by, char to) {
	if (numOfDisks == 1) {
		printf("원판 1을 %c 에서 %c 로 이동\n", from, to);
	}
	else {
		HanoiTower(numOfDisks - 1, from, to, by);
		printf("원판 %d을(를) %c 에서 %c로 이동", numOfDisks, from, to);
		HanoiTower(numOfDisks - 1, by, from, to);
	}
}

int main() {
	HanoiTower(3, 'A', 'B', 'C');
}

3.5. C++

#!syntax cpp
#include <iostream>
using namespace std;

void move(int from, int to)
{
    cout << from << " -> " << to << '\n';
}

void hanoi(int n, int from, int by, int to)
{
    if(n == 0) return;
    hanoi(n - 1, from, to, by);
    move(from, to);
    hanoi(n - 1, by, from, to);
}

3.6. Python

#!syntax python
def hanoi(number_of_disks_to_move, from_, to_, via_):
    if number_of_disks_to_move == 1:
        print(from_, "->", to_)
    else:
        hanoi(number_of_disks_to_move-1, from_, via_, to_)
        print(from_, "->", to_)
        hanoi(number_of_disks_to_move-1, via_, to_, from_)

3.7. Visual Prolog

class hanoi
   predicates
       hanoi : (unsigned N).
end class hanoi

implement hanoi
   domains
       pole = string.

   clauses
       hanoi(N) :- move(N, "left", "centre", "right").

   class predicates
       move : (unsigned N, pole A, pole B, pole C).
   clauses
       move(0, _, _, _) :- !.
       move(N, A, B, C) :- 
           move(N-1, A, C, B),
           stdio::writef("move a disc from % pole to the % pole\n", A, C),
           move(N-1, B, A, C).
end implement hanoi

goal
   console::init(),
   hanoi::hanoi(4).

3.8. Swift

#!syntax swift
import Foundation

func hanoi(_ n: Int, from a: Int, to b: Int, by c: Int) {
    if n==1 {
        print("Move 1 from \(a) to \(b)")
    }
    else {
        hanoi(n-1, from: a, to: b, by: c)
        print("Move \(n) from\(a) to\(b)")
        hanoi(n-1, from: c, to: b, by: a)
    }
}

3.9. HTML & JavaScript

• 화면 구현 - https://ssgi.kr/tower-of-hanoi
• 코드 내용 - https://github.com/Sinseiki/tower-of-hanoi-autoplay/blob/main/index.html

4. 기타