//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<n; ++i)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;
using ll = int64_t;
using ld = long double;
using P = pair<int, int>;
using vs = vector<string>;
using vi = vector<int>;
using vvi = vector<vi>;
template<class T> using PQ = priority_queue<T>;
template<class T> using PQG = priority_queue<T, vector<T>, greater<T> >;
const int INF = 0xccccccc;
const ll LINF = 0xcccccccccccccccLL;
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);}
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);}
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) { return is >> p.first >> p.second;}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) { return os << p.first << ' ' << p.second;}

struct SCC {
  struct csr {
    vector<int> start, elist;
    csr(int n, const vector<pair<int, int>> &edges)
      : start(n+1), elist(edges.size()) {
        for(pair<int, int> e:edges) {
          start[e.first+1]++;
        }
        for(int i = 1; i <= n; i++) {
          start[i] += start[i-1];
        }
        vector<int> counter = start;
        for(pair<int, int> e:edges) {
          elist[counter[e.first]++] = e.second;
        }
    }
  };
  int n;
  vector<pair<int, int>> edges;
  SCC(int n_) : n(n_) {}
  void add(int from, int to) {edges.emplace_back(from, to);}
  pair<int, vector<int>> scc_ids() {
    csr g(n, edges);
    int now_ord = 0, group_num = 0;
    vector<int> used, low(n), ord(n, -1), ids(n);
    used.reserve(n);
    auto dfs = [&](auto self, int v)->void {
      low[v] = ord[v] = now_ord++;
      used.push_back(v);
      for(int i = g.start[v]; i < g.start[v+1]; i++) {
        int to = g.elist[i];
        if(ord[to] == -1) {
          self(self, to);
          low[v] = min(low[v], low[to]);
        }
        else {
          low[v] = min(low[v], ord[to]);
        }
      }
      if(low[v] == ord[v]) {
        while(true) {
          int u = used.back();
          used.pop_back();
          ord[u] = n;
          ids[u] = group_num;
          if(u == v) break;
        }
        group_num++;
      }
    };
    for(int i = 0; i < n; i++) {
      if(ord[i] == -1) dfs(dfs, i);
    }
    for(int &x:ids) {
      x = group_num - 1 - x;
    }
    return {group_num, ids};
  }
  vector<vector<int>> scc() {
    pair<int, vector<int>> ids = scc_ids();
    int group_num = ids.first;
    vector<int> counts(group_num);
    for(int x:ids.second) counts[x]++;
    vector<vector<int>> groups(group_num);
    for(int i = 0; i < group_num; i++) {
      groups[i].reserve(counts[i]);
    }
    for(int i = 0; i < n; i++) {
      groups[ids.second[i]].push_back(i);
    }
    return groups;
  }
};

//SCC is needed

struct two_sat {
  int n;
  vector<bool> boolean_val;
  SCC scc;
  two_sat():n(0), scc(0) {}
  two_sat(int n_):n(n_), boolean_val(n_), scc(n_<<1) {}

  void add(int i, bool ii, int j, bool jj) {
    scc.add(i + (ii?0:n), j + (jj?n:0));
    scc.add(j + (jj?0:n), i + (ii?n:0));
  }
  bool satisfiable() {
    vector<int> id = scc.scc_ids().second;
    for(int i = 0; i < n; i++) {
      if(id[i] == id[i+n]) return false;
      boolean_val[i] = id[i] < id[i+n];
    }
    return true;
  }
};

template <class S, class F>
struct SegTreeL {
  using FX = function<S(S, S)>;
  using FA = function<S(S, F)>;
  using FF = function<F(F, F)>;
  int n;
  FX fx;
  FA fa;
  FF ff;
  const S es;
  const F ef;
  vector<S> dat;
  vector<F> laz;
  SegTreeL(int n_, FX fx_, FA fa_, FF ff_, S es_, F ef_)
    : fx(fx_), fa(fa_), ff(ff_), es(es_), ef(ef_) {
      n = 1;
      while(n_ > n) n <<= 1;
      dat.assign(n*2-1, es);
      laz.assign(n*2-1, ef);
  }
  inline int chld(int k) {return k*2+1;}
  inline int chrd(int k) {return k*2+2;}
  void set(int i, S s) {dat[i+n-1] = s;}
  void build() {
    for(int k = n-2; k >= 0; k--) dat[k] = fx(dat[chld(k)], dat[chrd(k)]);
  }
  void eval(int k) {
    if(laz[k] == ef) return;
    if(k < n-1) {
      laz[chld(k)] = ff(laz[chld(k)], laz[k]);
      laz[chrd(k)] = ff(laz[chrd(k)], laz[k]);
    }
    dat[k] = fa(dat[k], laz[k]);
    laz[k] = ef;
  }
  void update(int a, int b, F x, int k, int l, int r) {
    eval(k);
    if(a <= l and r <= b) {
      laz[k] = ff(laz[k], x);
      eval(k);
    }
    else if(a < r and l < b) {
      update(a, b, x, chld(k), l, (l+r)>>1);
      update(a, b, x, chrd(k), (l+r)>>1, r);
      dat[k] = fx(dat[chld(k)], dat[chrd(k)]);
    }
  }
  void update(int a, int b, F x) {update(a, b, x, 0, 0, n);}
  S query(int a, int b, int k, int l, int r) {
    eval(k);
    if(r <= a or b <= l) return es;
    else if(a <= l and r <= b) return dat[k];
    else {
      S vl = query(a, b, chld(k), l, (l+r)>>1);
      S vr = query(a, b, chrd(k), (l+r)>>1, r);
      return fx(vl, vr);
    }
  }
  S query(int a, int b) {return query(a, b, 0, 0, n);}
  //debug
  inline const S operator[](const int i) {return query(i, i+1);}
  void print() {for(int i = 0; i < n; i++) cout << (*this)[i] << (i == n-1?'\n':' ');}
};

#define M 4010

//head

int n, m;
vi pink[M];
bitset<M/2> check;
auto fx = [](set<int> a, set<int> b)->set<int> {
  set<int> res;
  set_union(a.begin(), a.end(), b.begin(), b.end(), inserter(res, res.end()));
  return res;
};
SegTreeL<set<int>, set<int>> rng(M>>1, fx, fx, fx, set<int>(), set<int>());

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m;
  two_sat TS(n);
  rep(i, n) {
    check = 0;
    int l, r;
    cin >> l >> r;
    set<int> u = rng.query(l, r+1);
    for(int x:u) {
      if(x >= n) {
        TS.add(i, false, x-n, true);
      }
      else {
        TS.add(i, false, x, false);
      }
    }
    u = rng.query(m-1-r, m-l);
    for(int x:u) {
      if(x >= n) {
        TS.add(i, true, x-n, true);
      }
      else {
        TS.add(i, true, x, false);
      }
    }
    rng.update(l, r+1, set<int>({i}));
    rng.update(m-1-r, m-l, set<int>({i+n}));
  }
  cout << (TS.satisfiable()?"YES\n":"NO\n");
}