Recollection

Time limit1sMemory limit1024 MB

Summary

Given N classes with student ID lists, count the students who appear in at least M of the classes.

Level: Easy2 of 10
Topics: Hash map, Implementation
Solved: No attempts yet

Problem

Professor Noh has taught $N$ classes so far at Seoul Cyber University, in the Department of Big Data and Information Security, the Department of Artificial Intelligence, the Department of Computer Engineering, and others. One day, while looking back on the students who took his classes, he wondered how many students had taken $M$ or more of his classes.

There were too many classes and students to keep track of at a glance, so he asked you to analyze them. Given the student IDs for each class, find the number of students who meet the condition.

Input

The first line contains $N$ and $M$ . $(1 \le N \le 100;$ $1 \le M \le N)$

The next $2 \times N$ lines describe the $N$ classes in order. The first line of class $i$ contains the number of students $K_i$ in that class. The second line contains the $K_i$ student IDs of class $i$ , separated by single spaces. $(1 \le K_i \le 240)$

Each student ID consists of 8 digits and always starts with $1$ . No student appears more than once in the same class.

Output

Print the number of students who took $M$ or more classes.

Hint

Seoul Cyber University has at most $240$ students in a class, and undergraduate student IDs start with $1$ .

Examples2

Example 1

Input

3 2
3
12500001 12500002 12500003
5
12500001 12500003 12500005 12500007 12500009
4
12500001 12500004 12500007 12500010

Expected output

Example 2

Input

3 2
3
12599999 12599998 12599997
1
12599996
2
12599995 12599994

Expected output