vault backup: 2023-09-29 14:33:01

Algo/Séminaire/Exercices seminaire.md

@@ -476,3 +476,32 @@ let prime n =
 		in (n = 2) || (n mod 2 = 1 and check n 3)
 ```
 
+## Hanoi
+```Ocaml
+(* displays moves: source -> destination *)
+
+let move source destination =
+  print_int source ;
+  print_string " -> " ;
+  print_int destination ;
+  print_newline()
+;;  
+
+let hanoi n =
+  let rec play n source auxiliary destination =
+    if n = 1 then
+      move source destination
+    else
+    begin
+      play (n-1) source destination auxiliary;
+      move source destination;
+      play (n-1) auxiliary source destination
+    end
+  in
+  if n < 0 then
+    invalid_arg "Hanoi: number of disks invalid"
+  else
+    play n 1 2 3 (* Appel initial avec les piquets source, auxiliaire et destination *)
+;;
+hanoi 3;; (* Pour déplacer 3 disques de la tige 1 à la tige 3 *)
+```