1, 2, 3, 4, ..., 2007, 2008 these 2008 integers, how many numbers can be selected at most, so that the difference between any two of the selected numbers is not equal to 1, and not equal to 4.
1，2，3，4，…，2007，2008这2008个整数中，最多能选出多少个数，使得选出来的数中任意两个的差都不等于1，且不等于4．
<gadget id="calculator">2_000 / 10</gadget>
<output>200</output>

<gadget id="calculator">200 + 1</gadget>
<output>201</output>

<gadget id="calculator">201 * 4</gadget>
<output>804</output>

<result>804</result>