1466：Girls and Boys

题目描述

In the second year of the university somebody started a study on the romantic relations between the students. The relation "romantically involved" is defined between one girl and one boy. For the study reasons it is necessary to find out the maximum set satisfying the condition: there are no two students in the set who have been "romantically involved". The result of the program is the number of students in such a set.

输入解释

The input contains several data sets in text format. Each data set represents one set of subjects of the study, with the following description:

the number of students
the description of each student, in the following format
student_identifier:(number_of_romantic_relations) student_identifier1 student_identifier2 student_identifier3 ...
or
student_identifier:(0)

The student_identifier is an integer number between 0 and n-1 (n <=500 ), for n subjects.

输出解释

For each given data set, the program should write to standard output a line containing the result.

输入样例

7
0: (3) 4 5 6
1: (2) 4 6
2: (0)
3: (0)
4: (2) 0 1
5: (1) 0
6: (2) 0 1
3
0: (2) 1 2
1: (1) 0
2: (1) 0

输出样例

5
2

该题目是Virtual Judge题目，来自北京大学POJ

题目来源 Southeastern Europe 2000

源链接： POJ-1466

最后修改于 2020-10-29T06:04:54+00:00 由爬虫自动更新

共提交 0 次

通过率 --%

时间上限	内存上限
5000	10000