PROGRAMMING:Social Clusters

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 $$N$$ ($$\le 1000$$), 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:
```in
eight
3: 2 7 10
1: 4
2: 5 3
1: 4
1: 3
1: 4
4: 6 8 1 5
1: 4
```
### Sample Output:
```out
three
4 3 1
```







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