给出下列【代码】注释标注的代码的输出结果。import java.io.*;
public class E {
public static void main(String args[]){
int n=-1;
File f = new File("hello.txt");
char[] a ="你好hello".toCharArray();
try{ FileWriter out=new FileWriter(f);
out.write(a);
out.close();
FileReader in=new FileReader(f);
char [] tom= new char[4];
int m = in.read(tom);
String s=new String(tom,0,m);
System.out.printf("%d:%s",m,s); //【代码】
}
catch(IOException e) {}
}
}