/*
 * class ArraySwap
 * burton rosenberg
 * march 2002
*/
  
class ArraySwap extends ReadInteger {

   int [] theArray = null ;


   void swap( int i, int j ) {
      if ( theArray==null ) {
         return ;
      }
      if ( i<0 || j<0 || i>=theArray.length || j>=theArray.length ) {
         return ;
      }
      int t ;
      t = theArray[i] ;
      theArray[i] = theArray[j] ;
      theArray[j] = t ;
   }


   void printArray() {
      System.out.println("theArray:") ;
      if ( theArray!=null ) {
         for ( int i=0; i<theArray.length; i++ ) {
            System.out.println(theArray[i]) ;
         }
      }
   }

   void fillArray( int n ) {
      if ( theArray==null || theArray.length!=n ) {
          theArray = new int [n] ;
      }
      for ( int i=0; i<theArray.length; i++ ) {
         theArray[i] = readInteger("Integer? ") ;
      }
   }

}