source_code: //package codeforces;
  
  import java.util.*;
  
  public class Main {
      class team implements Comparable<team>{
          int pro,time;
  
          public int compareTo(team oth) {
              if(pro>oth.pro)
                  return -1;
              if(pro==oth.pro&&time<oth.time)
                  return -1;
              // TODO Auto-generated method stub
              return 1;
          }
          
      }
      Scanner scan=new Scanner(System.in);
      void run(){
          int n=scan.nextInt();
          int k=scan.nextInt()-1;
          team tm[]=new team[n];
          for(int i=0;i<n;i++){
              tm[i]=new team();
              tm[i].pro=scan.nextInt();
              tm[i].time=scan.nextInt();
          }
          Arrays.sort(tm);
          int sum=0;
          
          for(int i=k;i>=0;i--)
              if(tm[i].pro==tm[k].pro&&tm[i].time==tm[k].time)
                  sum++;
          for(int i=k;i<n;i++)
              if(tm[i].pro==tm[k].pro&&tm[i].time==tm[k].time)
                  sum++;
          System.out.println(sum-1);
      }
      public static void main(String args[]) {
           
          new Main().run();
      }
  
  }