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Pair.java

class Pair 
{
     private int hi;
     private int lo;
     
     public Pair()
     {
          this.hi = 0;
          this.lo = 0;
     }
     
     public synchronized void inclo ()
     {
          while (this.lo <= this.hi)
          {
               try {
                    this.wait();
               }
               catch (java.lang.InterruptedException ex) {
               }
          }
          this.lo = (this.lo + 1);
     }
     
     public synchronized void inchi ()
     {
          this.hi = (this.hi + 1);
          this.notify();
     }
}

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