public class Test {
public static void main(String[] args) {
Count myCount = new Count();
int times = 0;

for (int i=0; i<100; i++)
increment(myCount, times);

System.out.println("myCount.count = " + myCount.count);
System.out.println("times = "+ times);
}

public static void increment(Count c, int times) {
c.count++;
times++;
}
}

class Count {
int count;

Count(int c) {
count = c;
}

Count() {
count = 1;
}
}

class A {
int v = 10;

public void print() {
int v = 100;
System.out.println(v);
}
}

public class Main {
public static void main(String[] args) {
A a=new A();
a.print();
}
}

class Student{
int age;
}

在主方法中，有如下两段程序代码A和B：

 int a;        //变量a是局部变量
System.out.println(a); //A段代码

 Student student=new Student();
System.out.println(student.age); //B段代码

关于A和B两段代码的合法性，说法正确的是：（      ）。

1．class  HasStatic{
2． private static int x=100；
3． public static void main(String[ ] args){
4． HasStatic hs1=new HasStatic( );
5． hs1.x++;
6． HasStatic hs2=new HasStatic( );
7． hs2.x++;
8． hs1=new HasStatic( );
9． hs1.x++;
10． HasStatic.x--;
11． System.out.println(“x=”+x);
12． }
13． }

public class Ref {
public static void main(String[] args){
Ref r = new Ref();
r.amethod(r);
}
public void amethod(Ref r){
int i = 99;
multi(r);
System.out.println(i);
}
public void multi(Ref r){
r.i = r.i * 2;
}
}