Hanoi Towers

program lab_1_1_3;{  This program solves the Tower of Hanoi puzzle  Matyushin Vyacheslav    (group 07-PO1)}const N = 10;	 type	 circle_array	= array [1..N] of Integer;procedure PrintArray (a	: circle_array);var	 i : Integer;begin		 for i := 1 to N do			Write (a[i],' ');	 Writeln;end; { PrintArray }procedure PrintArrays (a, b, c : circle_array);begin	 Write ('A: ');	 PrintArray (a);	 Write ('B: ');	 PrintArray (b);	 Write ('C: ');	 PrintArray (c);	 Writeln;end; { PrintArrays }function ArrayIsEmpty (a : circle_array) : boolean;var	 i, flag	: Integer;begin	 flag := 0;	 for i := 1 to N do	 begin			if a[i] <> 0 then			begin				 flag := 1;				 break;			end;	 end;	 if flag = 0 then			ArrayIsEmpty := true	 else			ArrayIsEmpty := false;end; { ArrayIsEmpty }function ArrayHeigth (a	: circle_array) : Integer;var	 i, flag : Integer;begin	 flag := 0;	 if ArrayIsEmpty (a) then			ArrayHeigth := 0	 else	 begin			for i := 1 to N do				 if a[i] = 0 then				 begin						ArrayHeigth := i - 1;						flag := 1;						break;				 end;			if flag = 0 then				 ArrayHeigth := N;	 end;end; { ArrayHeigth }procedure Swap (var a, b : circle_array);var ha, hb : Integer;begin	 ha := ArrayHeigth (a);	 hb := ArrayHeigth (b);	 if (ha = 0) and (hb <> 0) then	 begin			a[1] := b[hb];			b[hb] := 0;	 end;	 if (hb = 0) and (ha <> 0) then	 begin			b[1] := a[ha];			a[ha] := 0;	 end;	 	 if a[ha] < b[hb] then	 begin			b[hb + 1] := a[ha];			a[ha] := 0;	 end;	 	 if b[hb] < a[ha] then	 begin			a[ha + 1] := b[hb];			b[hb] := 0;	 end;end; { Swap }procedure Solve (var a, b, c : circle_array; var d : Integer);{moving right: d = 1, moving left: d = 0}var	 ha, hb, hc	: Integer;begin	 ha := ArrayHeigth (a);	 hb := ArrayHeigth (b);	 hc := ArrayHeigth (c);	 if (ha = 0) and (hb = 0) then			Writeln ('Finished')	 else			if d = 1 then			begin				 c[hc + 1] := a[ha];				 a[ha] := 0;				 PrintArrays (a, b, c);				 				 b[hb + 1] := a[ha - 1];				 a[ha - 1] := 0;				 PrintArrays (a, b, c);				 b[hb + 2] := c[hc + 1];				 c[hc + 1] := 0;				 PrintArrays (a, b, c);				 c[hc + 1] := a[ha - 2];				 a[ha - 2] := 0;				 PrintArrays (a, b, c);				 a[ha - 2] := b[hb + 2];				 b[hb + 2] := 0;				 PrintArrays (a, b, c);				 c[hc + 2] := b[hb + 1];				 b[hb + 1] := 0;				 PrintArrays (a, b, c);				 c[hc + 3] := a[ha - 2];				 a[ha - 2] := 0;				 PrintArrays (a, b, c);				 Swap (a, b);				 d := 0;				 PrintArrays (a, b, c);				 Solve (a, b, c, d);			end			else			begin				 a[ha + 1] := c[hc];				 c[hc] := 0;				 PrintArrays (a, b, c);				 b[hb + 1] := c[hc - 1];				 c[hc - 1] := 0;				 PrintArrays (a, b, c);				 b[hb + 2] := a[ha + 1];				 a[ha + 1] := 0;				 PrintArrays (a, b, c);				 a[ha + 1] := c[hc - 2];				 c[hc - 2] := 0;				 PrintArrays (a, b, c);				 c[hc - 2] := b[hb + 2];				 b[hb + 2] := 0;				 PrintArrays (a, b, c);				 a[ha + 2] := b[hb + 1];				 b[hb + 1] := 0;				 PrintArrays (a, b, c);				 a[ha + 3] := c[hc - 2];				 c[hc - 2] := 0;				 PrintArrays (a, b, c);				 Swap (b, c);				 d := 1;				 PrintArrays (a, b, c);				 				 Solve (a, b, c, d);			end;end; { Solve }var	 a, b, c			: circle_array;	 i, direction	: Integer;	 begin	 Writeln ('Number of circles: ', N);	 	 for i := 1 to N do	 begin			a[i] := N - i + 1;			b[i] := 0;			c[i] := 0;	 end;	 direction := 1;	 PrintArrays (a, b, c);	 Solve (a, b, c, direction);end.