4004.六度空间理论

 1 #include<iostream>
 2 #include<cstring>
 3 using namespace std;
 4 #define maxn 100
 5 
 6 typedef struct node
 7 {
 8     int data;
 9     struct node *next;
10 } Node;
11 
12 Node *V[maxn];//邻接表
13 int visit[maxn];
14 
15 void BFS(int s, int n)
16 {
17     int count = 1;
18     Node *p;
19     memset(visit, 0, sizeof(visit));
20     int Queue[maxn];
21     int front = 0, rear = 0, last = 0;
22     Queue[0] = s;
23     visit[s] = 1;
24     int six = 0;
25     while (front <= last)
26     {
27         p = V[Queue[front++]]->next;
28         while (p)//单层遍历，一个人的所有朋友遍历，Queue存储其友
29         {
30             if (!visit[p->data])
31             {
32                 count++;//计数加一
33                 visit[p->data] = 1;//改变访问状态
34                 Queue[++rear] = p->data;//队尾赋值
35             }
36             p = p->next;
37         }
38         if (front>last)//判断此人的一度朋友是否遍历，如果遍历结束，进入其二度朋友
39         {
40             last = rear;
41             six++;
42             if (six == 6)
43                 break;
44         }
45     }
46     printf("%d: %.2f%%\n", s, count*100.0 / n);
47 }
48 
49 int main()
50 {
51     int n, m;
52     int x, y;
53     Node *p;
54     while (1)
55     {
56         cin >> n >> m;
57         if (!n&&!m)break;
58         for (int i = 1; i <= n; i++)
59         {
60             V[i] =new Node;
61             V[i]->data = i;
62             V[i]->next = NULL;
63         }//set up 邻接表 index
64         while (m--)
65         {
66             cin>>x>>y;
67             p = new Node;
68             p->data = y;
69             p->next = V[x]->next;
70             V[x]->next = p;//y follow V[x]
71             p = new Node;
72             p->data = x;
73             p->next = V[y]->next;
74             V[y]->next = p;//x follow V[y]
75         }
76         for (int i = 1; i <= n; i++)
77             BFS(i, n);
78     }
79     return 0;
80 }