一步一步复习数据结构和算法基础-深度优先搜索

以下图为例进行深搜：

我们以无向图为例

由于深度搜索的结果不唯一，我们以 1 为初始搜索顶点，得出的结果是

1 2 4 5 6 7 3 8

程序如下：

#include<stdio.h>#include<stdlib.h>#include<string.h>#define number 20typedef struct node{int info;//图的节点存放的信息，可随时变动}GraphNode;typedef struct{GraphNode matrix[number+1][number+1];//构造邻接矩阵int vexs[number+1];//顶点向量int vertex,edge;//顶点个数、弧个数}Graph;int visited[number+1];//创建图void CreatGraph(Graph *G){int i,k;int x,y,data;int vertex,edge;printf("输入图的顶点个数和边的个数.\n");scanf("%d%d",&vertex,&edge);G->vertex = vertex;G->edge = edge;printf("输入图的每个顶点.\n");for(i=1;i<=vertex;i++)scanf("%d",&G->vexs[i]);for(i=1;i<=vertex;i++)for(k=1;k<=vertex;k++)G->matrix[i][k].info = 0;printf("请输入 %d 条边的横坐标、纵坐标、数值.\n",edge);for(i=1;i<=edge;i++){scanf("%d%d%d",&x,&y,&data);G->matrix[x][y].info=data;G->matrix[y][x].info=data;}}//找出给定顶点的位置int LocateVex(Graph *G,int V){int i;for(i=1;i<=G->vertex;i++)if(G->vexs[i] == V)return i;return -1;//失败返回-1}//打印图void DisplayGraph(Graph *G){int i,k;for(i=1;i<=G->vertex;i++){for(k=1;k<=G->vertex;k++)printf("%-4d ",G->matrix[i][k].info);printf("\n");}printf("\n");}void RecoverGraph(Graph *G){int i,k;for(i=1;i<=G->vertex;i++)for(k=1;k<=G->vertex;k++)G->matrix[i][k].info=0;memset(G->vexs,0,sizeof(G->vexs));G->vertex = G->edge = 0;}//找出指定顶点在图中的第一个邻接点int FirstAdjVex(Graph *G,int V){int temp,i;if((temp = LocateVex(G,V))==-1) return -1;//失败返回-1else{for(i=1;i<=G->vertex;i++)if(G->matrix[temp][i].info != 0)return i;}return -1;}int NextAdjVertex(Graph *G,int v,int w){int temp,i;if((temp=LocateVex(G,v)) == -1)return -1;for(i=w+1;i<=G->vertex;i++)if(G->matrix[temp][i].info)return i;return -1;}void DFS(Graph *G,int v){int w;visited[v]=1;printf("%d ",G->vexs[v]);for(w=FirstAdjVex(G,v);w>=0;w=NextAdjVertex(G,v,w))if(!visited[w])DFS(G,w);}void DFSTraverse(Graph *G){int i;for(i=1;i<=G->vertex;i++)visited[i]=0;for(i=1;i<=G->vertex;i++)if(!visited[i])DFS(G,i);}int main(){Graph G;CreatGraph(&G);DFSTraverse(&G);printf("\n");RecoverGraph(&G);return 0;}

测试结果如下：