1 #include <cstdlib>
2 #include <iostream>
3 #include <string.h>
4 using namespace std;
5 struct graph{
6 char map[500][20];
7 long data[500][500];
8 long vexnum,arcnum;
9 };
10
11 long d[500];//d[500]为度
12 long mount=0,p[500];//p[500]存储排序后的信息；
13
14
15
16 long find_number(char a[],graph &Mgraph)
17 {long long i;
18 for(i=0;i<mount;i++)
19 {if(strcmp(Mgraph.map[i],a)==0)
20 return i;
21 }
22 if(i==mount)
23 {strcpy(Mgraph.map[mount],a);mount++;return mount-1;}
24 }
25
26
27
28 long topsort(graph Mgraph)
29 {long f1,i,k=0,j=0;
30 long n=Mgraph.vexnum;
31 while(1)
32 {
33 for(i=0;((i<n)&&(d[i]!=0));i++);
34 if(i==n)
35 return 0;
36 for(f1=i,i++;i<n;i++)
37 {if(d[i]==0)
38 if(strcmp(Mgraph.map[i],Mgraph.map[f1])<0)
39 f1=i;
40 }
41
42 p[k++]=f1;if(k==n) return 1;
43 d[f1]=-1;
44 for(i=0;i<n;i++)
45 {d[i]-=Mgraph.data[f1][i];}
46 }
47 }
48
49 long input(graph &Mgraph)
50 {long n,m,i,j,k,f1,f2;char a[20],b[20];
51
52 printf("%15s","");cout<<"请输入图的顶点数";
53
54 cin>>n;Mgraph.vexnum=n;
55 printf("%15s","");cout<<"请输入图的边数";
56 cin>>m;Mgraph.arcnum=m;
57 mount=0; for(i=0;i<500;i++)
58 strcpy(Mgraph.map[i],"");
59 memset(Mgraph.data,0,sizeof(Mgraph.data));
60 memset(d,0,sizeof(d));
61 memset(p,0,sizeof(p));
62 printf("%15s","");cout<<"请按提示输入相邻的顶点"<<endl;
63
64 for(i=1;i<=m;i++)
65 { printf("%15s","");cout<<"起点：";cin>>a;
66 printf("%15s","");cout<<"终点：";cin>>b;
67 f1=find_number(a,Mgraph);f2=find_number(b,Mgraph);
68 if(Mgraph.data[f1][f2]==0)//防止平行边
69 {Mgraph.data[f1][f2]=1;d[f2]+=1;}
70 }
71 return n;
72 }
73
74
75 int main(int argc, char *argv[])
76 {long n,i;
77 graph Mgraph;
78 n=input(Mgraph);
79 int k=topsort(Mgraph);
80 system("cls");
81 if(!k)
82 {printf("%15s","");cout<<"impossible"<<endl;}
83 else
84 {printf("%15s","");cout<<"排序结果为"<<endl;
85 for(i=0;i<n;i++)
86 {printf("%28s","");cout<<Mgraph.map[p[i]]<<endl;}
87
88 }
89 system("PAUSE");
90 return EXIT_SUCCESS;
91 }
92
93
