九宫排字问题（又称八数码问题）是人工智能当中有名的难题之一。问题是在 3×3 方格盘上，放有八个数码，剩下第九个为空，每一空格其上下左右的数码可移至空格。问题给定初始位置和目标位置，要求通过一系列的数码移动，将初始位置转化为目标位置。本文介绍用普通搜索方法、双向广度搜索和启发式搜索如何缩短寻找路径的时间，以及各算法间的利与弊。-Jiugong typesetting problem (also known as eight digital problem) is one of famous problems of artificial intelligence.Problem is on the 3 x3 grid, there are eight digital, put the remaining nine is empty, each Spaces around the top and bottom of digital can be moved to a space.Problem given the initial position and target position, made by a series of digital mobile, converting the initial position to the target location.In this paper, double breadth search using ordinary search method and heuristic search how to shorten the time of the search path, as well as the advantages and disadvantages between these algorithms.