ReturnStatement 在哪个包 大家指点一下

public class ex_4_9
<br>{
<br>  String evaluate(int score)
<br>   {
<br>     String s;
<br>     if(score&gt;=90) s="very good";
<br>        else if(score&gt;=80) s="good";
<br>    else if(score&gt;=70) s="middle";
<br>       else if(score&gt;=60) s="pass";
<br>          else s="fail";
<br>      return s;
<br> }
<br> public static void main(String args[])
<br>  {
<br>  int score=(int)(Math.random()*100);
<br>  System.out.println(score);
<br>  ReturnStatement rs = new ReturnStatement();
<br>  System.out.println(rs.evalute(score));
<br>  }
<br> }

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