关键词: 快速搜索（QS）算法, 改进的快速搜索（I_QS）算法, 性能, 模式匹配

Abstract: The paper suggests an Improved Quick Search（I_QS） algorithm for string matching based on the detailed analysis of Quick Search（QS） algorithm. The I_QS algorithm uses every adjacent two characters of pattern string to make up of a string and constitutes a string table, then confirms the position of strings. It uses back three characters of the current matching window to determine the distance of next shif. To analyse the performance of the I_QS algorithm, some experiments are done from three aspects which are matched time, trial times and characters’ numbers through the number of different pattern strings. The experimental results show that because the I_QS algorithm can maximum limit to move to right, so it can reduce the times of moving and the time of matching. The I_QS algorithm enhances the algorithm’s efficiency.

Key words: Quick Search（QS） algorithm, Improved Quick Search（I_QS） algorithm, performance, pattern matching