Why is this sync example not working?

Playing with sync, I basically have two cuncurrent threads executing a method of the same object, but I'm probably getting something wrong.

Given this piece of code

public class Test {
    public static void main(String... args) throws InterruptedException{
        new Test();
    }

    Test() throws InterruptedException{

        Stuff s = new Stuff();

        Th t1 = new Th(1,s);
        Th t2 = new Th(2,s);

        t1.start();
        Thread.sleep(1000);
        t2.start();
    }
}

class Stuff{
    public Integer count=0;

    void doStuff(int threadId){
        System.out.println(threadId + ": in doStuff");
        synchronized (count) {
            count += 100;

            if (threadId == 1) {
                try {Thread.sleep(3000);} 
                catch (InterruptedException e) {e.printStackTrace();}
            }

            System.out.println(threadId + ": count = " + count);
        }
    }
}

class Th extends Thread{

    public Stuff s;
    public int id;

    @Override
    public void run(){
        System.out.println(id+": thread run");
        s.doStuff(id);
    }

    Th(int id_,Stuff s_){
        s=s_;
        id=id_;
        System.out.println(id+": thread created");
    }
}

      

        
        
        
      

    

I am getting this output

    1: thread created
    2: thread created
    1: thread run
    1: in doStuff
    2: thread run
    2: in doStuff
    2: count = 200
    1: count = 200

Why t1

does "200" print? Shouldn't you t2

wait t1

for a synchronized block to execute before being able to acquire a lock on count

and then execute the block?