精確多重字串比對問題是給予一個來源字串，以及多個目標字串，將所有目標字串在來源字串中精確出現的結束位置找到。藉由將所有來源字串上指定長度的子字串儲存於參考字串樹上，使得此參考樹上的所有內部節點，都存在一個參考字串，精確多重字串比對問題可以有效率地得到答案—藉由搜尋此參考字串樹可找到每個目標字串精確出現的位置。在這篇論文中，我們設計與分析建立參考字串樹與搜尋參考字串樹的演算法，並使用位元平行運算增加建立與搜尋的效能。我們以果蠅的DNA序列以及聖經作為來源字串做實驗，並與目前幾種壓縮字尾樹演算法與壓縮字尾陣列演算法做比較，實驗結果顯示我們參考字串樹演算法的速度效能優於這些演算法。我們所提參考字串樹的概念並不複雜、在精確多重串比對問題上卻有效率佳、具彈性且效能穩定的表現。

Given a text T and a set of r patterns P_1,P_2,⋯,P_r, the exact multiple pattern matching problem reports the ending positions of all occurrences of P_i in T for 1≤i≤r. By transforming all substrings with a fixed length of T into a reference tree such that each internal node stores a reference string, the exact multiple pattern matching problem can be efficiently solved by searching patterns in the tree via the guidance of the reference strings. We design and analysis elegant algorithms to construct the reference tree (the preprocessing phase) and to search patterns in the tree (the searching phase) using bitwise operations. The experiments involving problem instances from the DNA sequence and the English language are conducted to compare the performance of our approach against those of the compressed suffix tree and suffix array algorithms. The computational results demonstrate the advantage of our approach over these algorithms. In spite of the simplicity, our approach is quite efficient, flexible and robust.

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