N-B-U-T Online Judge :: [1259] The Roll

[1259] The Roll
时间限制: 1000 ms　内存限制: 65535 K
问题描述
this week our school calls the roll everyday.I hate it,but have to accept it.And I heard a news,our leader would like to know which student id escaped most.there are many class(1 <= class <= 20),every class has X students,numbered from 1 to X,this number equals to their students id.That means every NO.1 student in every class has the same id. now I'll tell you the escaped ids in every class,your task is to statistic it and report to me.
输入
first there is a class number n,then followed with n lines,first number means the number in a class, the second number means t students escaped,then followed t numbers,means the id of these students.
输出
Look at Sample input,after calculate,the most escaped time is 2,so you print
"2 times:",and the id who escaped for two times.
Last line you should print the number who never escaped.
if 0 students escaped ,you shoulw first print"Nobody Skipped The Classes!",then print the number who never escaped.
Hint:there may exist repeat number in a class,exp: 40 5 1 2 2 3 4,then you should treat 2 as two times.
样例输入

3
40 5 1 6 11 24 33
45 3 3 23 43
50 2 7 43
2
40 0
50 0

2 times:43
1 time :1 3 6 7 11 23 24 33
good students:126
Nobody Skipped The Classes!
good students:90