分支界限法是由“分支”和“界限”策略两个部分组成，其中“分支”策略是对问题空间按照广度优先的策略进行搜索；“限界”策略是为了加速搜索速度而采用启发信息剪枝的策略。

使用分支限界法来解决单源最短路径问题时主要利用结点控制关系剪枝，在一般情况下，如果解空间树中以结点Y为根的子树中所含的解优于以结点X为根的子树中所含的解，则结点Y控制了结点X，以被控制的结点X为根的子树可以剪去。算法实现时，使用邻接矩阵表示图，二维数组存储图的邻接矩阵，使用数组记录源到各顶点的距离和路径上的前驱顶点。

-Branch and bound by the "branch" and "boundaries" strategy of two parts, one "branch" strategy is the problem of space in accordance with the breadth-first search strategy　"bound" strategy is to accelerate the search speed and the use of heuristic pruning strategy.

　Using the branch and bound method to solve the single-source shortest path problem between the main control by pruning nodes, in general, if the solution space to the tree root node Y is contained in the solution sub-tree nodes than to X is the root of the solution contained in the subtree, then Y control the end point node X, to be controlled node X is the root of the sub-tree can be cut. Algorithm, the use of adjacency matrix graph, two-dimensional array stored in the adjacency matrix, using an array of records from the source to the vertex distance and path of the precursor peak.