Achieve Efficient and Privacy-Preserving Compound Substring Query over Cloud

Algorithm 1

Build a position heap for the string .

(1)	initialize a root node as the position heap , where and ;
(2)	for each in do
(3)	;
(4)	for each in do
(5)	find the child of , where ;
(6)	if does exist then
(7)
(8)	else
(9)	insert a new child node for the ;
(10)	;
(11)	break;
(12)	end if
(13)	end for
(14)	end for
(15)	return ;