Rosetta Code

Towers of Hanoi

Solve Towers of Hanoi recursively and return each move in order.

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Sourcerosettacode/popular/towers_of_hanoi.vibe
def hanoi_moves(
  disks: int,
  from_peg: int,
  to_peg: int,
  spare_peg: int
) -> array<{ disk: int, from: int, to: int }>
  if disks == 0
    []
  else
    hanoi_moves(disks - 1, from_peg, spare_peg, to_peg) + [{ disk: disks, from: from_peg, to: to_peg }] + hanoi_moves(disks - 1, spare_peg, to_peg, from_peg)
  end
end

def run -> { move_count: int, moves: array<{ disk: int, from: int, to: int }> }
  moves = hanoi_moves(3, 1, 3, 2)
  {
    move_count: moves.length,
    moves: moves
  }
end

Output

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