程序在运行的时候,头次只显示了第一次浏览时的0,在刷新浏览器是,计数器不能正常按点击数目增加,请高手看看是程序哪里的问题导致这样的问题,谢谢了<?php
         $counterfile="counter.txt";
         if( !file_exists($counterfile))
 {
          $fw=fopen($counterfile,"w");
             fwrite($fw,0);
           fclose($fw);
 }
          function disp($counterfile)
    {
             $fp=fopen($counterfile,"r");
             $num=fread($fp,8);
             fclose($fp);
             $nun+=1;     
             echo "你是本站的第".$num."位游客<br>";
             $fpw=fopen($counterfile,"w");
             fwrite($fpw,$num);
             fclose($fpw);
      }
             disp($counterfile);?>