Creating an unsafe thread program

Question

good day all, please I've been battling with this program. what I will like to do is to find a way of increasing the value of the counter in the while loop (inside the run() method) until it comes to a point where “Unsafe operation detected” is printed to screen. Please could any one help me with this? here is my code:
class Counter implements Runnable
private int counter;
     boolean flag = false;
public int get()
     return counter;
public void set(int n)
     counter = n;
public void increment()
     int temp1 = counter;
          counter++;
          int temp2 = counter;
          if( temp1 == temp2 || (temp2-temp1) > 1 )
     setFlag();
     public boolean getFlag()
     return flag;
     public void setFlag()
     flag = true;
     public void run()
     set(0);
          while( get() < 10 )
          //counter++;
increment();
if (getFlag() == true )
System.out.println( "Unsafe operation detected" );
else
System.out.println( "Fortuitously executed successfully");
     public static void main(String[] args)
     Runnable myRun = new Counter();
          Thread t1 = new Thread(myRun);
          Thread t2 = new Thread(myRun);
          t1.start();
          t2.start();
}

Answer 1

Not only that, he got the answer here first, at 11:10, and still kept posting over there from 11:39, and got his first answer there at 11:46. Not our problem I guess but an amazing waste of everybody's time, including his own.