By Ricardo Oliveira, UFPR Brazil
Like many Computer Science students, you like to play the most popular electronic games nowadays: Liga of Legendas (LOL) and Contra-Strike (CS). Although you also play LOL, what you really like to do is to use all your skills to defeat the terrorist forces in Contra-Strike! You are so good at combating terror that you are often compared with the president of the USA who announced the capture of a famous real-life terrorist.
Since your skills are beyond compare, videos of your matches (your famous gameplays) appears often in UFPR Gaming, a webpage that publishes gameplays from the students of our university.
The page publishes many videos every day. Thus, it may be hard to find and count all your videos published already. However, since you are also a programmer, you decided to write a computer program to help you with this task. Given the list of gameplays published by the page, determine how many of them are videos of you playing Contra-Strike.
The input contains several test cases. The first line of each test case contains two integers N and I (1 ≤ N ≤ 104, 1000 ≤ I ≤ 9999), the number of gameplays published by the page and your university ID, respectively.
The next N lines describe the published videos. Each gameplay is described by two integers i and j (1000 ≤ i ≤ 9999, j=0 or 1), where i is the author’s university ID and j=0 if the gameplay is a Contra-Strike one, or j=1 if it is a Liga of Legendas one.
The input ends with end-of-file (EOF).
For each test case, print a single line containing a number indicating how many videos of you playing Contra-Strike were published by the page.
|Input Sample||Output Sample|