1107. Social Clusters (30)

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

#include<stdio.h>
#include<vector>
#include<algorithm>
#include<math.h>
using namespace std;
int ans[111][111];

bool cmp(int a,int b)
{
    return a > b;
}

struct node
{
    vector<int> child;
};

node Tree[100100];

int MIN = 100100;
int cnt = 0;
bool vis[1100];
vector<int> Fun[1100];
vector<int> stu[1100];
void DFS(int root,int& sum)
{
    for(int i = 0 ;i < stu[root].size();++i)
    {
        for(int k = 0 ;k < Fun[ stu[root][i] ].size();++k)
        {
            if(!vis[Fun[ stu[root][i] ][k]])
            {
                ++sum;
                vis[Fun[ stu[root][i] ][k]] = 1;
                DFS(Fun[ stu[root][i] ][k],sum);
            }
        }
    }
}


int main()
{
    int n,num,tem;
    double pri,rate;
    scanf("%d",&n);
    for(int i = 1 ;i <= n ;++i)
    {
        scanf("%d",&num);
        getchar();
        for(int k = 0 ;k < num;++k)
        {
            scanf("%d",&tem);
            Fun[tem].push_back(i);
            stu[i].push_back(tem);
        }
    }
    vector<int> vv;
    int cnt = 0;;
    for(int i = 1;i <= n ;++i)
    {
        if(!vis[i])
        {
            int sum = 0;
            ++cnt;
            DFS(i,sum);
            vv.push_back(sum);
        }
    }
    sort(vv.begin(),vv.end(),cmp);
    printf("%d
",vv.size());
    for(int i = 0 ;i < vv.size();++i)
    {
        if(i == 0) printf("%d",vv[0]);
        else printf(" %d",vv[i]);
    }
    printf("
");
    return 0;
}