图算法系列-图的简单实现

 1 struct Edge{
 2 int v,w;
 3 Edge(int a=-1,int b=-1):v(a),w(b){}
 4 };
 5 
 6 class Graph
 7 {
 8 private:
 9 //
10 public:
11 Graph(int,bool);
12 ~Graph();
13 int V() const;//顶点
14 int E() const;//边
15 bool directed() const;//是否有方向
16 int insert(Edge);
17 int remove(Edge);
18 bool edge(int,int);
19 //迭代器
20 class adjIterator
21 {
22 public:
23 adjIterator(const Graph&,int);
24 int begin();
25 int next();
26 bool end();
27 };
28 };

 1 class DenseGraph
 2 {
 3 public:
 4 DenseGraph(int v,bool digraph=false):adj(v),Vcnt(v),Ecnt(0),diGraph(digraph){
 5 for(int i=0;i<v;++i)
 6 adj[i].assign(v,false);//将邻接矩阵初始化为false
 7 }
 8 int V() const{
 9 return Vcnt;
10 }
11 int E() const{
12 return Ecnt;
13 }
14 bool directed() const{
15 return diGraph;
16 }
17 void insert(Edge e)
18 {
19 int v=e.v,w=e.w;
20 if(adj[v][w]==false) Ecnt++;
21 adj[v][w]=true;
22 if(!digraph) adj[w][v]=true;
23 }
24 void remove(Edge e)
25 {
26 
27 int v=e.v,w=e.w;
28 if(adj[v][w]==true) Ecnt--;
29 adj[v][w]=false;
30 if(!digraph) adj[w][v]=false;
31 }
32 bool edge(int v,int w) const
33 {
34 return adj[v][w];
35 }
36 class adjIterator;
37 friend class adjIterator;
38 
39 private:
40 int Vcnt;//顶点数
41 int Ecnt;//边数
42 bool diGraph;//是否有向图
43 vector< vector<bool> > adj;//邻接矩阵
44 };
45 
46 //邻接矩阵的迭代器，返回顶点vertex的下一个相邻的顶点
47 class DenseGraph::adjIterator
48 {
49 public:
50 adjIterator(const DenseGraph &g,int vertex):
51 G(g),v(vertex),i(-1){}
52 int begin()
53 {
54 i=-1;
55 return next();
56 }
57 int next()
58 {
59 for(i++;i<G.V();++i)
60 if(G.adj[v][i]==true) return i;
61 return -1;
62 }
63 bool end()
64 {
65 return i>=G.V();
66 }
67 private:
68 const DenseGraph &G;
69 int i,v;
70 }；

 1 class SparseGraph()
 2 {
 3 public:
 4 SparseGraph(int v,bool digraph=false):
 5 Vcnt(v),Ecnt(0),diGraph(digraph){
 6 adj.assign(v,0);
 7 }
 8 SparseGraph(const SparseGraph& G);
 9 ~SparseGraph();
10 int V() const{
11 return Vcnt;
12 }
13 int E() const{
14 return Ecnt;
15 }
16 bool directed(){
17 return digraph;
18 }
19 //往图中插入一条边
20 void insert(Edge e){
21 int v=e.v,w=e.w;
22 adj[v]=new node(w,adj[v]);
23 if(!diGraph) adj[w]=new node(v,adj[w]);
24 Ecnt++;
25 }
26 void remove(Edge e);
27 bool Edge(int v,int w) const;
28 class adjIterator;//邻接表的迭代器
29 friend class adjIterator;//把迭代器类设置为友元类
30 private:
31 int Vcnt,Ecnt;
32 bool diGraph;
33 struct node
34 {
35 int v;
36 node* next;
37 node(int x,node* t):v(x),next(t){}
38 };
39 typedef node* link;
40 vector<link> adj;//邻接表
41 }；
42 
43 //邻接表迭代器的实现
44 class SparseGraph::adjIterator
45 {
46 public:
47 adjIterator(const SparseGraph& g,int v):
48 G(g),v(v),curLink(0){}
49 adjIterator(const adjIterator&);
50 ~adjIterator();
51 int begin(){
52 curLink=adj[v];
53 return curLink?curLink-v:-1;
54 
55 }
56 int next(){
57 if(curLink) curLink=curLink->next;
58 return curLink?curLink->v:-1;
59 }
60 bool end(){
61 return curLink==0;
62 }
63 private:
64 const SparseGraph& G;
65 int v;//顶点编号
66 link curLink;
67 };

 1 template <class Graph> class SearchPath
 2 {
 3 
 4 public:
 5 SearchPath(const Graph& g,int v,int w):
 6 G(g),visited(g.V(),false){
 7 found=search(v,w);
 8 }
 9 bool existed() const
10 {
11 return found;
12 }
13 private:
14 const Graph& G;
15 vector<bool> visited;
16 bool found;
17 bool search(int v,int w)
18 {
19 if(v=w) return true;
20 visited[v]=true;

21 typename Graph::adjIterator ite(G,v);
22 for(int t=ite.begin();!ite.end();t=ite.next())
23 if(!visited[t])
24 if(search(t,w)) return true;
25 return false;
26 }
27 };