邻接表 构造 有向/无向 图/网

//create graph by adjacent list
#include<iostream>
#define MAX 20
using namespace std;
//定义图的类型
typedef enum{DG,UDG,DN,UDN}GraphKind;
//定义弧结点
typedef struct ArcNode{
    int vex;
    struct ArcNode *nextArc;
    int info;//权值 
}ArcNode;
//定义表头(顶点)结点
typedef struct{
    int vex;
    ArcNode *firstArc; 
}VexNode;
//定义领接表存储的图
typedef struct{
    int vexnum,arcnum;
    VexNode vertices[MAX];
    GraphKind kind;
}ALGraph;
//返回顶点v在图中的位置(下标)
int Locate(const ALGraph &G,int vex){
    for(int i=0;i<G.vexnum;++i){
        if(G.vertices[i].vex==vex)
            return i;
    }
    return INT_MAX;
}
//清空一个图，释放堆分配的内存
bool deleteGraph(ALGraph &G){
    for(int i=0;i<G.vexnum;++i){
        while(G.vertices[i].firstArc){
            ArcNode *q=G.vertices[i].firstArc;
            G.vertices[i].firstArc=q->nextArc;
            delete q;
        }
    }
    return true;
}
//创造有向图
bool createDG(ALGraph &G){
    cout<<"\nInput "<<G.vexnum<<" Vertices : ";
    for(int i=0;i<G.vexnum;++i){
        cin>>G.vertices[i].vex;
        G.vertices[i].firstArc=NULL;
    }
    cout<<"Input "<<G.arcnum<<" Arcs : "<<endl;
    for(int i=0;i<G.arcnum;++i){
        int v1,v2;
        int p=Locate(G,v1);
        if(p>=INT_MAX) return false;
        ArcNode* q=new ArcNode;
        q->vex=v2;
        q->info=INT_MAX;
        q->nextArc=G.vertices[p].firstArc;
        G.vertices[p].firstArc=q;
        q=NULL;
    }
    return true;
}
//创造无向图
bool createUDG(ALGraph &G){
    cout<<"\nInput "<<G.vexnum<<" Vertices : ";
    for(int i=0;i<G.vexnum;++i){
        cin>>G.vertices[i].vex;
        G.vertices[i].firstArc=NULL;
    }
    cout<<"Input "<<G.arcnum<<" Arcs : "<<endl;
    for(int i=0;i<G.arcnum;++i){
        int v1,v2;
        cin>>v1>>v2;
        int p=Locate(G,v1);
        int q=Locate(G,v2);
        if(p>=INT_MAX||q>=INT_MAX) return false;
        ArcNode *temp=new ArcNode;
        temp->vex=v2;
        temp->nextArc=G.vertices[p].firstArc;
        temp->info=INT_MAX;
        G.vertices[p].firstArc=temp;
        temp=new ArcNode;
        temp->vex=v1;
        temp->info=INT_MAX;
        temp->nextArc=G.vertices[q].firstArc;
        G.vertices[q].firstArc=temp;
    }
    return true;
}
//创造有向网
bool createDN(ALGraph &G){
    cout<<"\nInput "<<G.vexnum<<" Vertices : ";
    for(int i=0;i<G.vexnum;++i){
        cin>>G.vertices[i].vex;
        G.vertices[i].firstArc=NULL;
    }
    cout<<"Input "<<G.arcnum<<" Arcs : "<<endl;
    for(int i=0;i<G.arcnum;++i){
        int v1,v2,w;
        cin>>v1>>v2>>w;
        int p=Locate(G,v1);
        if(p>=INT_MAX) return false;
        ArcNode *temp=new ArcNode;
        temp->vex=v2;
        temp->nextArc=G.vertices[p].firstArc;
        temp->info=w;
        G.vertices[p].firstArc=temp;
    }
    return true;
}
//创造无向网
bool createUDN(ALGraph &G){
    cout<<"\nInput "<<G.vexnum<<" Vertices : ";
    for(int i=0;i<G.vexnum;++i){
        cin>>G.vertices[i].vex;
        G.vertices[i].firstArc=NULL;
    }
    cout<<"Input "<<G.arcnum<<" Arcs : "<<endl;
    for(int i=0;i<G.arcnum;++i){
        int v1,v2,w;
        cin>>v1>>v2>>w;
        int p=Locate(G,v1);
        int q=Locate(G,v2);
        if(p>=INT_MAX||q>=INT_MAX) return false;
        ArcNode *temp=new ArcNode;
        temp->info=w;
        temp->vex=v2;
        temp->nextArc=G.vertices[p].firstArc;
        G.vertices[p].firstArc=temp;
        temp=new ArcNode;
        temp->info=w;
        temp->vex=v1;
        temp->nextArc=G.vertices[q].firstArc;
        G.vertices[q].firstArc=temp;
    }
    return true;
}
//接口，创造图
bool createGraph(ALGraph &G){
    switch(G.kind){
        case DG:
            return createDG(G);
        case UDG:
            return createUDG(G);
        case DN:
            return createDN(G);
        case UDN:
            return createUDN(G);
        default:
            return false;
    }
}
//打印邻接链表创造的图
void displayALGraph(const ALGraph &G){
    for(int i=0;i<G.vexnum;++i){
        cout<<G.vertices[i].vex<<" ";
        ArcNode *p=G.vertices[i].firstArc;
        while(p){
            cout<<"->"<<p->vex;
            if(p->info < INT_MAX)
                cout<<"("<<p->info<<")";
            p=p->nextArc;
        }
        cout<<endl;
    }
}
//测试
int main(){
    ALGraph graph;
    int kind;
    
    cout<<"Create A Graph in Adjacent List ."<<endl;
    cout<<"1-DG , 2-UDG , 3-DN , 4-UDN"<<endl;
    cout<<"Graph Kind : ";
    cin>>kind;
    if(kind==1)graph.kind=DG;
    else if(kind==2) graph.kind=UDG;
    else if(kind==3) graph.kind=DN;
    else if(kind==4) graph.kind=UDN;
    else{
        cout<<"Invalid Graph Type.";
        return 0;
    }
    cout<<"Vertices Number : ";
    cin>>graph.vexnum;
    cout<<"Arcs Number : ";
    cin>>graph.arcnum;
    
    if (createGraph(graph)){
        cout<<"\nthe Adjacent Matrix is : "<<endl;
        displayALGraph(graph);
    }else cout<<"Invalid input , None Matching Vertex."<<flush;
    if(deleteGraph(graph)){
        cout<<"\n\nAll Deleted.";
    }
}