图的存储结构之数组表示法

        由于图中顶点间的关系(弧或边)无规律，故对图的存储较之表或树要复杂的多，需要根据图的具体应用来构造图的存储结构。

常用的存储表示有“数组表示法”、“邻接表”、“十字链表”和“邻接多重表”。

 

数组表示法

图的数组表示法又称“邻接矩阵”(Adjacency Matrix)表示法。   G = (V，R)

用两个数组来存储图G：

一个数组(一维)存储G中顶点集合V；另一个数组(二维)映像图中顶点间的关系集R，该二维数组就是所谓的邻接矩阵。该邻接矩阵是一个n阶方阵。

 

#include <stdio.h>#include <stdlib.h>#include <string.h>//memset//#include <strings.h>//bzerotypedef struct _adjm_graph_{void *relation;int vn;}MGraph;MGraph *init_ajmgraph(int vn);int free_adjmgraph(MGraph *graph);int add_edge(MGraph *graph, int vx, int vy);int show_adjmgraph(MGraph *graph);int main(){MGraph *graph = NULL;int v2, v1;int vn = 0;puts("input number of vertexes:");while( 1 != scanf("%d", &vn))getchar();graph = init_ajmgraph(vn);#if 1puts("input the relation of vertexes:");while(1){while( 2 != scanf("%d%d", &v1, &v2))getchar();if(v1 == v2)break;add_edge(graph, v1, v2);}show_adjmgraph(graph);#endiffree_adjmgraph(graph);return 0;}MGraph *init_ajmgraph(int vn){MGraph *graph = NULL;graph = (MGraph *)malloc(sizeof(MGraph));graph->relation = malloc(vn * vn);memset(graph->relation, 0, vn * vn);//bzero(graph->relation, vn * vn);graph->vn = vn;return graph;}int free_adjmgraph(MGraph *graph){free(graph->relation);free(graph);return 0;}int add_edge(MGraph *graph, int vx, int vy){char (*relation)[graph->vn] = graph->relation;if(vx < 0 || vy < 0 || vx >= graph->vn || vy >= graph->vn)return -1;relation[vx][vy] = 1;//GNU C//p[vx * graph->vn + vy] = 1;//ISO C90}int show_adjmgraph(MGraph *graph){int i,j;int vn = graph->vn;char (*relation)[vn] = graph->relation;for(i = 0; i < vn; i ++){printf("v%d: ", i);for(j = 0; j < vn; j ++){if(relation[i][j] == 1)printf(" v%d,", j);}puts("\b ");}}