source_code: import java.io.*;
  import java.util.*;
  
  public class A {
  
  	class Team implements Comparable<Team>{
  		int p, t;
  		public Team(int p, int t) {
  			this.p = p;
  			this.t = t;
  		}
  		public int compareTo(Team other) {
  			if (this.p != other.p) return other.p - this.p;
  			return this.t - other.t;
  		}
  	}
  	
  	public void solve() throws IOException {
  		int n = nextInt();
  		int K = nextInt() - 1;
  		Team[] team = new Team[n];
  		for (int i = 0; i < n; i++) 
  			team[i] = new Team(nextInt(), nextInt());
  		
  		Arrays.sort(team);
  		int ans = -1;
  		int pre = 0;
  		for (int i = 1; i < n; i++)
  			if (team[i].compareTo(team[i - 1]) != 0) {
  				if (K >= pre && K < i) {
  					ans = i - pre;
  					break;
  				}
  				pre = i;
  			}
  		if (ans == -1) ans = n - pre;
  		writer.println(ans);
  	}
  
  	public static void main(String[] args) throws FileNotFoundException {
  		new A().run();
  	}
  
  	BufferedReader reader;
  	StringTokenizer tokenizer;
  	PrintWriter writer;
  
  	public void run() {
  		try {
  			long tbegin = System.currentTimeMillis();
  			reader = new BufferedReader(new InputStreamReader(System.in));
  			//reader = new BufferedReader(new InputStreamReader(new FileInputStream("test.inp")));
  			tokenizer = null;
  			writer = new PrintWriter(System.out);
  			//writer = new PrintWriter(new FileOutputStream("test.out"));
  			solve();
  			//reader.close();
  			//System.out.println(System.currentTimeMillis() - tbegin + "ms");
  			writer.close();
  		} catch (Exception e) {
  			e.printStackTrace();
  			System.exit(1);
  		}
  	}
  
  	int nextInt() throws IOException {
  		return Integer.parseInt(nextToken());
  	}
  
  	long nextLong() throws IOException {
  		return Long.parseLong(nextToken());
  	}
  
  	double nextDouble() throws IOException {
  		return Double.parseDouble(nextToken());
  	}
  
  	String nextToken() throws IOException {
  		while (tokenizer == null || !tokenizer.hasMoreTokens()) {
  			tokenizer = new StringTokenizer(reader.readLine());
  		}
  		return tokenizer.nextToken();
  	}
  
  }
  