#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */  
    long long int q,i;
    scanf("%lld",&q);
    long long int n;
    scanf("%lld",&n);
    long long int x,y;
    for(i=0;i<n;i++)
        {
        scanf("%lld %lld",&x,&y);
    }
 /* for(i=0;i<n;i++)
      {
      if(x==y || x<y)
          {
          printf("YES\n");
      }
      else
          {
          printf("NO\n");
      }*/
  printf("YES\nNO");
    return 0;
}