06-Figure 1 list connected sets (25 points) (implemented in the C language neighbor list) and 06-adjacent

06-Figure 1 list connected sets (25 points) (implemented in the C language neighbor list) and 06-adjacent

Address: https://pta.patest.cn/pta/test/558/exam/4/question/9495

Because the number of edges E <(n * (n-1)/2, I chose the adjacent table implementation. The priority queue is implemented using the cyclic queue;

DFS basic ideas:

1: select a vertex to indicate that the vertex has been accessed;

2: select the next vertex to determine whether other neighboring contacts of the vertex (the access sequence is from small to large) have been accessed;

3: Repeat 2nd to know that all vertices have been accessed.

The pseudocode is as follows:

DFS( Vertex v ){       Visit( V );     Visited[V] = true;     foreach(  v->neighbor )        if ( Visited[v->neighbor ] == false )                DFS(v->neighbor );}

BFS basic ideas:

1: select a point to join the team and visit this point, marking that the site has been visited;

2: Leave the team and place all the neighboring points not visited at this pointAccessAnd join the team;

3: Repeat the second point until the queue is empty;

The pseudocode is as follows:

BFS ( Vertex v ){       Visit( v );    Visited[v] = true;    EnQueue(Q, v);           while ( !IsEmpty(Q) )     {        w = DeQueue(Q);          foreach ( w->neighor )            if ( Visited[w->neighor] == false )             {                 Visit( w->neighor );                Visited[w->neighor] = true;                EnQueue(Q, w->neighor);            }    } }        

Code

1 # include <stdio. h> 2 # include <stdlib. h> 3 # include <stdbool. h> 4 # include <string. h> 5 # include <dos. h> 6 7 # define MaxVertexNum 10 8 9 typedef int ElementType; 10 typedef int Position; 11 12 typedef struct QNode {13 ElementType * Data; /* array of storage elements */14 Position Front, Rear;/* queue header and tail pointer */15 int MaxSize;/* maximum queue capacity */16} QNode, * Queue; 17 18 19 typedef struct ENode 20 {21 int ivex; // The vertex position pointed to by the edge 22 struct ENode * next; 23} ENode, * PENode; 24 25 typedef int VertexType; 26 27 typedef struct VNode 28 {29 VertexType data; 30 ENode * first_edge; 31} VNode; 32 33 typedef struct LGraph 34 {35 int vexnum; // Number of vertices in the graph 36 int edgnum; // Number of edges in the graph 37 VNode * vexs; // array of vertex storage 38} LGraph; 39 40 bool TAG; // output format 41 bool visited [MaxVertexNum]; 42 43 LGraph * LGraph_new (); 44 void LGraph_destroy (LGraph * G); 45 void LGraph_insert (ENode ** head, int ivex); 46 void ResetVisit (); 47 void DFS (LGraph * G, int vex); 48 void BFS (LGraph * G, int vex); 49 void ListComponents (LGraph * G, void (* func) (LGraph * G, int vex )); 50 51 // basic operations of the priority Queue 52 Queue CreateQueue (int MaxSize); 53 bool IsFull (Queue Q); 54 bool AddQ (Queue Q, ElementType X ); 55 bool IsEmpty (Queue Q); 56 ElementType DeleteQ (Queue Q); 57 5 8 int main () 59 {60 LGraph * G = LGraph_new (); 61 ResetVisit (); 62 ListComponents (G, DFS); 63 ResetVisit (); 64 ListComponents (G, BFS); 65 system ("pause"); 66 return 0; 67} 68 69 void ListComponents (LGraph * G, void (* func) (LGraph * G, int vex )) 70 {71 int I; 72 for (I = 0; I <G-> vexnum; ++ I) 73 {74 if (visited [I] = false) 75 {76 (* func) (G, I); 77 printf ("} \ n"); 78 TAG = false; 79} 80} 8 1} 82 83 LGraph * LGraph_new () 84 {85 86 LGraph * G = (LGraph *) malloc (sizeof (LGraph); 87 scanf ("% d ", & G-> vexnum, & G-> edgnum); 88G-> vexs = (VNode *) malloc (G-> vexnum * sizeof (VNode); 89 int I, v1, v2; 90 for (I = 0; I <G-> vexnum; ++ I) 91 {92G-> vexs [I]. data = I; 93G-> vexs [I]. first_edge = NULL; 94} 95 for (I = 0; I <G-> edgnum; ++ I) 96 {97 scanf ("% d", & v1, & v2); 98 // because the vertex information is the vertex Coordinate 99 LGraph_insert (& G-> vexs [v1]. first_edge, v2); 100 LGraph_insert (& G-> vexs [v2]. first_edge, v1); 101} 102 return G; 103} 104 void ResetVisit () 105 {106 TAG = false; 107 memset (visited, false, sizeof (visited )); 109} 110 111 void LGraph_insert (ENode ** head, int ivex) 112 {113 ENode * pnew, * p1, * p2; 114 pnew = (ENode *) malloc (sizeof (ENode); 115 pnew-> ivex = ivex; 116 if (* head = NULL) 117 {118 * head = p New; 119 120 pnew-> next = NULL; 121} 122 else 123 {124 if (* head)-> ivex) // trouble with no header node 125 {126 pnew-> next = * head; 127 * head = pnew; 128} 129 else130 {131 for (p1 = * head, p2 = p1-> next; p2! = NULL; p1 = p2, p2 = p1-> next) 132 {133 if (p2-> ivex) 134 break; 135} 136 pnew-> next = p2; 137 p1-> next = pnew; 138} 139} 140 141 void DFS (LGraph * G, int vex) 142 {143 if (TAG = false) 145 {146 TAG = true; 147 printf ("{"); 148} 149 printf ("% d", vex); 150 visited [vex] = true; 151 ENode * temp = G-> vexs [vex]. first_edge; 152 while (temp! = NULL) 153 {154 if (visited [temp-> ivex] = false) 155 {156 DFS (G, temp-> ivex ); 157} 158 temp = temp-> next; 159} 160} 161 void BFS (LGraph * G, int vex) 162 {163 Queue Q = CreateQueue (G-> vexnum ); 164 if (TAG = false) 165 {166 TAG = true; 167 printf ("{"); 168} 169 printf ("% d", vex ); 170 visited [vex] = true; 171 AddQ (Q, vex); 172 while (! IsEmpty (Q) 173 {174 vex = DeleteQ (Q); 175 ENode * temp = G-> vexs [vex]. first_edge; 176 while (temp! = NULL) 177 {178 if (visited [temp-> ivex] = false) 179 {180 printf ("% d", temp-> ivex ); 181 visited [temp-> ivex] = true; 182 AddQ (Q, temp-> ivex); 183} 184 temp = temp-> next; 185} 186} 187 free (Q-> Data); 188 free (Q); 189} 190 191 192 // Queue basic operation 193 Queue CreateQueue (int MaxSize) 194 {195 Queue Q = (Queue) malloc (sizeof (struct QNode); 196 Q-> Data = (ElementType *) malloc (MaxSize * sizeof (ElementType )); 197 Q-> Front = Q-> Rear = 0; 198 Q-> MaxSize = MaxSize; 199 return Q; 200} 201 202 bool IsFull (Queue Q) 203 {204 return (Q-> Rear + 1) % Q-> MaxSize = Q-> Front); 205} 206 207 bool AddQ (Queue Q, ElementType X) 208 {209 if (IsFull (Q) {210 printf ("queue full"); 211 return false; 212} 213 else {214 Q-> Rear = (Q-> Rear + 1) % Q-> MaxSize; 215 Q-> Data [Q-> Rear] = X; 216 return true; 217} 218} 219 220 bool IsEmpty (Queue Q) 221 {222 return (Q-> Front = Q-> Rear ); 223} 224 225 ElementType DeleteQ (Queue Q) 226 {227 if (IsEmpty (Q) {228 printf ("Queue empty"); 229 return 0; 230} 231 else {232 Q-> Front = (Q-> Front + 1) % Q-> MaxSize; 233 return Q-> Data [Q-> Front]; 234} 235}View Code