#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>

#define FORR(i,b,e) for(int i=(b);i<(int)(e);++i)
#define FOR(i,e) FORR(i,0,e)
#define sortuniq(v) sort(v.begin(), v.end()), v.erase(unique(v.begin(),v.end()),v.end())
#define dump(var) cerr << #var ": " << var << "\n"
#define dumpc(con) for(auto& e: con) cerr << e << " "; cerr<<"\n"

typedef long long ll;
typedef unsigned long long ull;

const double EPS = 1e-6;
const int d4[] = {0, -1, 0, 1, 0};

using namespace std;

int N, M;

struct Row {
    int l, r;
    void flip() {
        int t = M - 1 - l;
        l = M - 1 - r;
        r = t;
    }
    bool operator<(const Row &o) const {
        return l != o.l? l < o.l: r < o.r;
    }
};


int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    cin >> N >> M;
    vector<Row> row(N);
    FOR(i, N) {
        cin >> row[i].l >> row[i].r;
        if (row[i].l >= M/2) row[i].flip();
    }
    sort(row.begin(), row.end());

    vector<int> w(M, -1);
    FOR(i, N) {
        bool overlap = false;
        FORR(j, row[i].l, row[i].r+1) {
            if (w[j] >= 0) {
                overlap = true;
                break;
            }
        }
        if (overlap) {
            row[i].flip();
            FORR(j, row[i].l, row[i].r+1) {
                if (w[j] >= 0) {
                    goto FAILURE;
                }
            }
        }
        FORR(j, row[i].l, row[i].r+1) w[j] = i;
    }
    // dumpc(w);
    cout << "YES" << endl;
    return 0;

    FAILURE:
    cout << "NO" << endl;

    return 0;
}