int distance( pq )
	tree pq;
	{ return( pq==NULL ? 0 : pq->dist ); };

	fixdist( pq )
	tree pq;
	{
	tree temp;
	if ( distance(pq->left) < distance(pq->right) ) {
		temp = pq->right;
		pq->right = pq->left;
		pq->left = temp;
		};
	pq->dist = distance(pq->right) + 1;
	};