1107. Social Clusters (30)

Posted 2020-06-16

When register on a social network, you are always asked to specify your hobbies in order to find some potential friends with the same hobbies. A "social cluster" is a set of people who have some of their hobbies in common. You are supposed to find all the clusters.

Input Specification:

Each input file contains one test case. For each test case, the first line contains a positive integer N (<=1000), the total number of people in a social network. Hence the people are numbered from 1 to N. Then N lines follow, each gives the hobby list of a person in the format:

K_i: h_i[1] h_i[2] ... h_i[K_i]

where K_i (>0) is the number of hobbies, and h_i[j] is the index of the j-th hobby, which is an integer in [1, 1000].

Output Specification:

For each case, print in one line the total number of clusters in the network. Then in the second line, print the numbers of people in the clusters in non-increasing order. The numbers must be separated by exactly one space, and there must be no extra space at the end of the line.

Sample Input:

8
3: 2 7 10
1: 4
2: 5 3
1: 4
1: 3
1: 4
4: 6 8 1 5
1: 4

Sample Output:

3
4 3 1

 1 #include<stdio.h>
 2 #include<vector>
 3 #include<algorithm>
 4 #include<math.h>
 5 using namespace std;
 6 int ans[111][111];
 7 
 8 bool cmp(int a,int b)
 9 {
10     return a > b;
11 }
12 
13 struct node
14 {
15     vector<int> child;
16 };
17 
18 node Tree[100100];
19 
20 int MIN = 100100;
21 int cnt = 0;
22 bool vis[1100];
23 vector<int> Fun[1100];
24 vector<int> stu[1100];
25 void DFS(int root,int& sum)
26 {
27     for(int i = 0 ;i < stu[root].size();++i)
28     {
29         for(int k = 0 ;k < Fun[ stu[root][i] ].size();++k)
30         {
31             if(!vis[Fun[ stu[root][i] ][k]])
32             {
33                 ++sum;
34                 vis[Fun[ stu[root][i] ][k]] = 1;
35                 DFS(Fun[ stu[root][i] ][k],sum);
36             }
37         }
38     }
39 }
40 
41 
42 int main()
43 {
44     int n,num,tem;
45     double pri,rate;
46     scanf("%d",&n);
47     for(int i = 1 ;i <= n ;++i)
48     {
49         scanf("%d",&num);
50         getchar();
51         for(int k = 0 ;k < num;++k)
52         {
53             scanf("%d",&tem);
54             Fun[tem].push_back(i);
55             stu[i].push_back(tem);
56         }
57     }
58     vector<int> vv;
59     int cnt = 0;;
60     for(int i = 1;i <= n ;++i)
61     {
62         if(!vis[i])
63         {
64             int sum = 0;
65             ++cnt;
66             DFS(i,sum);
67             vv.push_back(sum);
68         }
69     }
70     sort(vv.begin(),vv.end(),cmp);
71     printf("%d\n",vv.size());
72     for(int i = 0 ;i < vv.size();++i)
73     {
74         if(i == 0) printf("%d",vv[0]);
75         else printf(" %d",vv[i]);
76     }
77     printf("\n");
78     return 0;
79 }