There is an electronic frog at point A on a straight line. From point A, it jumps 1 unit length to the left, then jumps 3 unit lengths to the right, then jumps 5 unit lengths to the left, and then jumps 7 units to the right. unit length, then jump to the left for 9 unit lengths, and so on, the distance between the frog's 2009th landing point and A is ________ unit lengths.
在一条直线上的点A处有一只电子青蛙，它从A点开始先向左跳1个单位长度，接着向右跳3个单位长度，然后向左跳5个单位长度，接着向右跳7个单位长度，然后向左跳9个单位长度，如此类推，则青蛙第2009次的落点与A的距离是________个单位长度．
<gadget id="calculator">2 * 2_009</gadget>
<output>4_018</output>

<gadget id="calculator">4_018 - 1</gadget>
<output>4_017</output>

<gadget id="calculator">2_008 / 2</gadget>
<output>1_004</output>

<gadget id="calculator">1_004 * 2</gadget>
<output>2_008</output>

<gadget id="calculator">4_017 - 2_008</gadget>
<output>2_009</output>

<result>2_009</result>