Finding the shortest path, such as delivery by courier, must be done quickly in the shortest distance and time, so it involves the shortest path problem of the graph. Then, Dijkstra algorithm is produced, which is a classic shortest path algorithm. The basic idea is to set a set S to store the vertices that find the shortest path. The initial state of S only contains the source point V of VI ∈. It is assumed that the path from V to S is the shortest. Then, every time the shortest path V is obtained, VK is added to the set S, and paths V, VK and VI are compared with the original hypothesis. Taking the shortest path as the shortest path, the above process is repeated until all the vertices in set V are added to set S. When there are more network nodes and more network edges, there are shortcomings such as large memory consumption and high time complexity, and Dijkstra algorithm cannot solve the shortest path problem with necessary point constraints well.
Then the topological sort, that is, the topological sort (Dag) of directed acyclic graphs. G is to arrange all the vertices in G into a linear sequence, so that any pair of vertices U and V in the graph, if the edge
Map coloring is a combination configuration and a division of a map polygon set. Assign a color to each surface of the map so that adjacent surfaces (edges with common boundaries) have different colors. This color distribution is called mapping coloring, or the set of mapping surfaces is divided into several subsets, so that any two edges in each subset are not adjacent, so that the faces in each subset can be colored with one color, which makes the colors used in different subsets different. Of all the coloring of graph M, the chromatic number with the least color is called the chromatic number of graph M, and the vertex coloring of graph or the normal coloring of vertex of graph with the same structure is the graph coloring of its dual graph.
In fact, graphs are widely used, and there are more than that. We can also learn concepts to better understand the application of graphics.