1 #include<stdio.h>
2 #include<stdlib.h>
3
4 #define MAX_VERTAX_SIZE 20
5 #define OK 1
6 #define ERROR 0
7
8 typedef int Status;
9 typedef char ElemType;
10
11 typedef struct EageNode{
12 int adjacentVertax;
13 struct EageNode* nextAdjacentVertax;
14 }EageNode, *EageNodePtr;
15
16 typedef struct VertaxNode{
17 ElemType data;
18 EageNodePtr firstEage;
19 }VertaxNode;
20
21 typedef struct GraphAL{
22 VertaxNode VertaxArray[MAX_VERTAX_SIZE];
23 int vertaxNum;
24 int eageNum;
25 }GraphAL;
26
27 //定义队列结构，用于图的广度优先遍历
28 typedef struct QueueNode{
29 ElemType data;
30 struct QueueNode* next;
31 }QueueNode, *QueueNodePtr;
32 typedef struct Queue{
33 QueueNodePtr front;
34 QueueNodePtr rear;
35 }Queue;
36 Status InitQueue(Queue* Q){
37 Q->front = (QueueNodePtr)malloc(sizeof(struct QueueNode));
38 if( !Q->front )
39 return ERROR;
40 Q->rear = Q->front;
41 Q->rear->next = NULL;
42 return OK;
43 }
44 Status EnterQueue(Queue *q, ElemType value){
45 QueueNode* n;
46 n = (QueueNode*)malloc(sizeof(struct QueueNode));
47 if( !n )
48 return ERROR;
49 n->data = value;
50 n->next = q->rear->next;
51 q->rear->next = n;
52 q->rear = n;
53 return OK;
54 }
55 Status DeleteQueue(Queue* q,ElemType* value){
56 if( q->front == q->rear )
57 return ERROR;
58 QueueNode* p;
59 p = q->front->next;
60 *value = p->data;
61 q->front->next = p->next;
62 free(p);
63 if( p == q->rear )
64 q->rear = q->front;
65 return OK;
66 }
67 int IsQueueEmpty(Queue q){
68 return q.front == q.rear ? OK : ERROR;
69 }
70 /*
71 int main(){
72 Queue q;
73 ElemType c;
74 InitQueue(&q);
75 EnterQueue(&q,'a');
76 EnterQueue(&q,'f');
77 EnterQueue(&q,'g');
78 EnterQueue(&q,'e');
79 DeleteQueue(&q,&c);
80 printf("%c \n", c);
81 printf("&&&&%d", IsQueueEmpty(q));
82 DeleteQueue(&q,&c);
83 printf("%c \n", c);
84 return 0;
85 }
86 */
87
88 //返回顶点v在G中的下标
89 int LocateVertax(GraphAL G, ElemType v){
90 int i;
91 for( i = 0; i < G.vertaxNum; i++ ){
92 if( G.VertaxArray[i].data == v )
93 return i;
94 }
95 return -1;
96 }
97 //通过下标得到元素的值
98 ElemType GetValueFromIndex(GraphAL G, int index){
99 return G.VertaxArray[index].data;
100 }
101 //创建邻接表无向图
102 Status CreateUDG_AdjacencyList(GraphAL* G){
103 int i;
104 ElemType v,w;
105 int index_v, index_w;
106 EageNodePtr vPtr,wPtr;
107 printf(" Create Undigraph\n");
108 printf("Please enter the number of Vertax and Eage: ");
109 scanf("%d %d%*c", &(G->vertaxNum), &(G->eageNum));
110
111 printf("ok, please input the value of %d Vertax\n", G->vertaxNum);
112 for( i = 0; i < G->vertaxNum; i++ ){
113 scanf("%c%*c", &(G->VertaxArray[i].data));
114 G->VertaxArray[i].firstEage = NULL;
115 }
116
117 for( i = 0; i < G->eageNum; i++ ){
118 printf("ok, please input the two Vertax of Eage %d (Sepearted by Space) :", i+1);
119 scanf("%c %c%*c", &v,&w); //一条边的两个顶点v w
120 index_v = LocateVertax(*G, v);
121 index_w = LocateVertax(*G, w);
122 wPtr = (EageNode*)malloc(sizeof(EageNode));
123 if( !wPtr )
124 return ERROR;
125 wPtr->adjacentVertax = index_w;
126 wPtr->nextAdjacentVertax = G->VertaxArray[index_v].firstEage;
127 G->VertaxArray[index_v].firstEage = wPtr;
128
129 vPtr = (EageNode*)malloc(sizeof(EageNode));
130 if( !vPtr )
131 return ERROR;
132 vPtr->adjacentVertax = index_v;
133 vPtr->nextAdjacentVertax = G->VertaxArray[index_w].firstEage;
134 G->VertaxArray[index_w].firstEage = vPtr;
135 }
136 return OK;
137 }
138 //在图G中找v的第一个邻接顶点,找到则返回该顶点在邻接表中的位置，若没有则返回-1
139 int FirstAdjacentVertax(GraphAL G, ElemType v){
140 int index_v;
141 index_v = LocateVertax(G, v);
142 if( G.VertaxArray[index_v].firstEage == NULL )
143 return -1;
144 else
145 return (G.VertaxArray[index_v].firstEage)->adjacentVertax;
146 }
147 //在图G中找v的从w开始的下一个相邻的顶点
148 int NextAdjacentVertax(GraphAL G, ElemType v, ElemType w ){
149 int index_v,index_w;
150 EageNodePtr p;
151 index_v = LocateVertax(G, v);
152 index_w = LocateVertax(G, w);
153 if( G.VertaxArray[index_v].firstEage == NULL )
154 return -1;
155 p = G.VertaxArray[index_v].firstEage; //p pointer to first node
156 while( p->nextAdjacentVertax != NULL ){
157 if( p->adjacentVertax == index_w )
158 return p->nextAdjacentVertax->adjacentVertax;
159 p = p->nextAdjacentVertax;
160 }
161 return -1;
162 }
163
164 //DFS深度优先遍历图:使用递归算法，算法思想：
165 // 1：从v顶点开始，visit(v),将其设置为已遍历
166 // 2: 获得v的第一个邻接顶点w，若其存在并且没有访问过，递归遍历；
167 // 3: 获得v的从w之后的邻接点，若其存在并且没有访问过，递归遍历；直到所有都访问过
168 int visitedArray[MAX_VERTAX_SIZE];
169 void visit(ElemType c){
170 printf("%c ", c);
171 }
172 Status DFS(GraphAL G, ElemType v){
173 ElemType w;
174 visit(v);
175 visitedArray[LocateVertax(G, v)] = 1;
176 for( w = GetValueFromIndex(G, FirstAdjacentVertax(G, v)); LocateVertax(G, w) != -1; w = GetValueFromIndex(G, NextAdjacentVertax(G, v, w))){
177 if( visitedArray[LocateVertax(G, w)] != 1 )
178 DFS(G, w);
179 }
180 return OK;
181 }
182 Status DFSTraverse(GraphAL G){
183 int i;
184 for( i = 0; i < G.vertaxNum; i++ )
185 visitedArray[i] = 0;
186 for( i = 0; i < G.vertaxNum; i++ )
187 if( visitedArray[i] != 1 )
188 DFS(G, GetValueFromIndex(G, i));
189 return OK;
190 }
191
192
193 //BFS(Breadth First Search)
194 Status BFS(GraphAL G){
195 int i,j;
196 Queue q;
197 ElemType c;
198 InitQueue(&q);
199 for(i = 0; i < G.vertaxNum; i++)
200 visitedArray[i] = 0;
201 for(i = 0; i < G.vertaxNum; i++){ //这个for实际执行的次数是连通分量的个数
202 if( visitedArray[i] == 0 ){
203 EnterQueue(&q, G.VertaxArray[i].data);
204 visitedArray[i] = 1;
205 while( IsQueueEmpty(q) != OK ){
206 DeleteQueue(&q, &c);
207 visit(c);
208 for( j = FirstAdjacentVertax(G, c); j != -1; j = NextAdjacentVertax(G, c, GetValueFromIndex(G, j))){
209 if( visitedArray[j] == 0 ){
210 EnterQueue(&q, GetValueFromIndex(G, j));
211 visitedArray[j] = 1;
212 }
213 }
214 }
215 }
216 }
217 }
218
219
220 //打印无向图的邻接表
221 void PrintUDG_AdjacentList(GraphAL G){
222 int i;
223 EageNodePtr p;
224 printf(" Adjacency List \n");
225 for( i = 0; i < G.vertaxNum; i++ ){
226 printf(" %d %c ",i, G.VertaxArray[i]);
227 p = G.VertaxArray[i].firstEage;
228 while( p != NULL ){
229 printf("-->%d", p->adjacentVertax);
230 p = p->nextAdjacentVertax;
231 }
232 printf("\n");
233 }
234 }
235 int main(){
236 GraphAL G;
237 CreateUDG_AdjacencyList(&G);
238 PrintUDG_AdjacentList(G);
239
240 printf(" DFS(Depth First Search) of UDG(Undigraph)\n");
241 DFSTraverse(G);
242
243 printf("\n BFS(Breadth First Search) of UDG(Undigraph)\n");
244 BFS(G);
245 return 0;
246 }
