import java.util.*;
import java.io.*;

public class Main {
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String[] first = br.readLine().split(" ", 2);
        int n = Integer.parseInt(first[0]);
        int m = Integer.parseInt(first[1]);
        PriorityQueue<Block> queue = new PriorityQueue<>();
        for (int i = 0; i < n; i++) {
            queue.add(new Block(m, br.readLine()));
        }
        int start = -1;
        while (queue.size() > 0) {
            Block b = queue.poll();
            if (start < b.left) {
                start = b.right;
            } else {
                b.reverse();
                if (start < b.left) {
                    queue.add(b);
                } else {
                    System.out.println("NO");
                    return;
                }
            }
        }
        System.out.println("YES");
    }
    
    static class Block implements Comparable<Block> {
        int size;
        int left;
        int right;
        
        public Block(int size, String line) {
            this.size = size;
            String[] arr = line.split(" ", 2);
            left = Integer.parseInt(arr[0]);
            right = Integer.parseInt(arr[1]);
            if (left > size - right - 1) {
                reverse();
            }
        }
        
        public int compareTo(Block another) {
            if (left == another.left) {
                return right - another.right;
            } else {
                return left - another.left;
            }
        }
        
        public void reverse() {
            int tmp = right;
            right = size - left - 1;
            left = size - tmp - 1;
        }
        
        public String toString() {
            return "size:" + size + " left:" + left + " right:" + right;
        }
    }
}