class PilotRobot
    attr_reader :x, :y, :l

    def initialize(x: 0, y: 0, l: 0)
        @x, @y, @l = x, y, l
    end

    def datainput
        begin
            @x = Integer(gets.chomp)
            @y = Integer(gets.chomp)
            @l = Integer(gets.chomp)
        rescue
            
        end
    end

    def pilot(x, y, l)
        action = 0
        
        # y方向の移動
        action += y.abs / l
        action += 1 if 0 < (y.abs % l)
        
        # x方向の移動
        action += x.abs / l
        action += 1 if 0 < (x.abs % l)
        
        # x方向の回転
        action += 1 if x != 0
        
        # y方向の回転
        if y < 0
          action += 1
          #action += 1 if x == 0
        end
        
        return (x == 0 and y == 0)? 0 : action
    end

    def dataoutput
        puts pilot(@x, @y, @l)
    end

    def run
        datainput
        dataoutput
    end
end

if $0 == __FILE__
    PilotRobot.new.run
end