用邻接矩阵表示图（代码）和简化版代码

 1 //用邻接矩阵表示图
 2 #include <stdio.h>
 3 #include <stdlib.h>
 4 #define MaxVertexNum 20
 5  
 6 typedef int WeightType;
 7 typedef char DataType;
 8 typedef struct GNode *PtrToGNode;
 9 typedef PtrToGNode MGraph;        //以邻接矩阵存储的图类型
10  
11 struct GNode {
12     int Nv;        //顶点数
13     int Ne;        //边数
14     WeightType G[MaxVertexNum][MaxVertexNum];
15     DataType Data[MaxVertexNum];    //存顶点的数据
16 };
17  
18  
19  
20 //初始化一个有VertexNUm个顶点但没有边的图
21 typedef int Vertex;    //用顶点下标表示顶点，为整型
22 MGraph CreateGraph(int VertexNum)
23 {
24     Vertex v, w;
25     struct GNode* Graph;
26     Graph = (MGraph)malloc(sizeof(struct GNode));
27     Graph ->Nv = MaxVertexNum;
28     Graph ->Ne = 0;
29  
30     //这里的默认编号从0开始，到（Graph->Nv - 1)
31     for (v = 0; v < Graph->Nv; v++)
32     for (w = 0; w < Graph->Ne; w++)
33         Graph->G[v][w] = 0;
34  
35     return Graph;
36 }
37  
38 //向MGraph中插入边
39 typedef struct ENode *PtrToENode;
40 struct ENode {
41     Vertex v1, v2;        //有向边<v2, v1>
42     WeightType Weight;    //权重
43 };
44 typedef PtrToENode Edge;
45  
46 void InsertEdge(MGraph Graph, Edge E)
47 {
48     //插入边<v1, v2>
49     Graph->G[E -> v1][E->v2] = E->Weight;
50  
51     //插入边<v2, v1>
52     Graph->G[E->v2][E->v1] = E->Weight;
53 }
54  
55 //完整地建立一个MGraph
56 MGraph BuildGraph()
57 {
58     MGraph Graph;
59     Edge E;
60     Vertex V;
61     int Nv, i;
62     scanf_s("%d", &Nv);
63     Graph = CreateGraph(Nv);
64     scanf_s("%d", &(Graph->Ne));
65     if (Graph->Ne != 0)
66     {
67         E = (Edge)malloc(sizeof(struct ENode));
68         for (i = 0; i < Graph->Ne; i++)
69             scanf_s("%d %d %d", &E->v1, &E->v2, &E->Weight);
70         InsertEdge(Graph, E);
71     }
72  
73     //
74     for (V = 0; V < Graph->Nv; V++)
75         scanf_s(" %c", Graph->Data[V]);
76  
77     return Graph;
78 }
79  
80  
81  
82 int main()
83 {
84  
85  
86     return 0;
87 }

简化版：

 1 //用邻接矩阵表示图
 2 #include <stdio.h>
 3 #include <stdlib.h>
 4  
 5 #define MaxN 20
 6 int G[MaxN][MaxN], Nv, Ne;
 7 void BuildGraph()
 8 {
 9     int i , j, v1, v2, w;
10     scanf("%d", &Nv);
11  
12     for (i = 0; i < Nv; i++)
13     for (j = 0; j < Nv; j++)
14         G[i][j] = 0;
15     scanf_s("%d", &Ne);
16     for (i = 0; i < Ne; i++)
17     {
18         scanf_s("%d %d %d", &v1, &v2, &w);
19         
20         G[v1][v2] = w;        //InsertEdge
21         G[v2][v1] = w;
22     }
23 }