利用深度遍历算法实现

int getNum(MGraph G) {

int i, count = 0;

for(i = 0; i < G.vexnum; i++)

visited[i] = false;

for(i = 0; i < G.vexnum; i++)

if(!visited[i]) {

count++;

DFS(G, i);

}

return count;

}

测试代码如下：

以下代码以邻接表作为图的存储方式

#include

#include

#define MAXVEX 10

typedef int VertexType;

typedef struct arcNode {

int adjvex;

struct arcNode *next;

} arcNode;

typedef struct vertexNode {

VertexType data;

arcNode *first;

} vertexNode, adjList[MAXVEX];

typedef struct {

adjList adjlist;

int vexnum, arcnum;

} ALGraph;

//邻接表初始化

void createALGraph(ALGraph &G) {

int i, j, k;

arcNode *e;

printf("输入顶点数和边数：\n");

scanf("%d%d", &G.vexnum, &G.arcnum);

for(i = 0; i < G.vexnum; i++) {

scanf("%d", &G.adjlist[i].data);

G.adjlist[i].first = NULL;

}

for(k = 0; k < G.arcnum; k++) {

printf("输入边(vi, vj)上的顶点序号：\n");

scanf("%d%d", &i, &j);

e = (arcNode *)malloc(sizeof(arcNode));

e->adjvex = i;

e->next = G.adjlist[j].first;

G.adjlist[j].first = e;

e = (arcNode *)malloc(sizeof(arcNode));

e->adjvex = j;

e->next = G.adjlist[i].first;

G.adjlist[i].first = e;

}

}

//深度优先遍历

int visited[MAXVEX];

void DFS(ALGraph G, int i) {

arcNode *p;

visited[i] = 1;

p = G.adjlist[i].first;

while(p) {

if(!visited[p->adjvex])

DFS(G, p->adjvex);

p = p->next;

}

}

//求连通分量

int getNum(ALGraph G) {

int i, count = 0; //记录连通分量个数

for(i = 0; i < G.vexnum; i++)

visited[i] = 0;

for(i = 0; i < G.vexnum; i++)

if(!visited[i]) {

count++;

DFS(G, i);

}

return count;

}

int main() {

ALGraph G;

createALGraph(G);

printf("%d", getNum(G));

return 0;

}