#pragma GCC optimize ("O3")
#pragma GCC target ("avx")
#include "bits/stdc++.h" // define macro "/D__MAI"

using namespace std;
typedef long long int ll;

#define debugv(v) printf("L%d %s => ",__LINE__,#v);for(auto e:v){cout<<e<<" ";}cout<<endl;
#define debugm(m) printf("L%d %s is..\n",__LINE__,#m);for(auto v:m){for(auto e:v){cout<<e<<" ";}cout<<endl;}
#define debuga(m,w) printf("L%d %s is => ",__LINE__,#m);for(int x=0;x<(w);x++){cout<<(m)[x]<<" ";}cout<<endl;
#define debugaa(m,w,h) printf("L%d %s is..\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[x][y]<<" ";}cout<<endl;}
#define debugaar(m,w,h) printf("L%d %s is..\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[y][x]<<" ";}cout<<endl;}
#define ALL(v) (v).begin(),(v).end()
#define repeat(l) for(auto cnt=0;cnt<(l);++cnt)
#define iterate(b,e) for(auto cnt=(b);cnt!=(e);++cnt)
#define MD 1000000007ll
#define PI 3.1415926535897932384626433832795
template<typename T1, typename T2>
ostream& operator <<(ostream &o, const pair<T1, T2> p) { o << "(" << p.first << ":" << p.second << ")"; return o; }

#define TIME chrono::system_clock::now()
#define MILLISEC(t) (chrono::duration_cast<chrono::milliseconds>(t).count())
namespace {
    std::chrono::system_clock::time_point ttt;
    void tic() { ttt = TIME; }
    void toc() { fprintf(stderr, "TIME : %lldms\n", MILLISEC(TIME - ttt)); }
    std::chrono::system_clock::time_point tle = TIME;
#ifdef __MAI
    void safe_tle(int msec) { assert(MILLISEC(TIME - tle) < msec); }
#else
#define safe_tle(k) ;
#endif
}

#ifdef __MAI
#define getchar_unlocked getchar
#define putchar_unlocked putchar
#endif
#ifdef __VSCC
#define getchar_unlocked _getchar_nolock
#define putchar_unlocked _putchar_nolock
#endif
namespace {
#define isvisiablechar(c) (0x21<=(c)&&(c)<=0x7E)
    class MaiScanner {
    public:
        template<typename T>
        void input_integer(T& var) {
            var = 0;
            T sign = 1;
            int cc = getchar_unlocked();
            for (; cc<'0' || '9'<cc; cc = getchar_unlocked())
                if (cc == '-') sign = -1;
            for (; '0' <= cc&&cc <= '9'; cc = getchar_unlocked())
                var = (var << 3) + (var << 1) + cc - '0';
            var = var*sign;
        }
        inline int c() { return getchar_unlocked(); }
        inline MaiScanner& operator>>(int& var) {
            input_integer<int>(var);
            return *this;
        }
        inline MaiScanner& operator>>(long long& var) {
            input_integer<long long>(var);
            return *this;
        }
        inline MaiScanner& operator>>(string& var) {
            int cc = getchar_unlocked();
            for (; !isvisiablechar(cc); cc = getchar_unlocked());
            for (; isvisiablechar(cc); cc = getchar_unlocked())
                var.push_back(cc);
        }
    };
}
MaiScanner scanner;


class Graph {
public:
    size_t n;
    vector<vector<int>> vertex_to;
    vector<vector<int>> vertex_from;

    Graph(size_t n) :n(n), vertex_to(n), vertex_from(n) {}

    void connect(int from, int to) {
        vertex_to[from].emplace_back(to);
        vertex_from[to].emplace_back(from);
    }
    void resize(size_t _n) {
        n = _n;
        vertex_to.resize(_n);
        vertex_from.resize(_n);
    }
};

class sat_2 {
public:
    size_t n;
    Graph graph;

    sat_2(size_t n) :n(n), graph(n * 2 + 1) {
    }

private:
    inline int _cv(int v) { return 0<v ? v : -v + n; }

    void _scc_dfs1(int v, vector<int>& ord, vector<int> &num, int k) {
        if (0 <= num[v]) return;
        num[v] = k;
        for (int to : graph.vertex_to[v]) {
            _scc_dfs1(to, ord, num, k);
        }
        ord.push_back(v);
    }
    void _scc_dfs2(int v, vector<int> &num, int k) {
        if (num[v] < 0) return;
        num[v] = -k;
        for (int to : graph.vertex_from[v]) {
            _scc_dfs2(to, num, k);
        }
    }
public:

    // 1 <= a <= n OR -1 >= a >= -n
    // 正ならばx_a，負ならばNOT x_aを表現．
    inline void emplace(int a, int b) {
        // assert(a!=0 && b!=0);
        graph.connect(_cv(-a), _cv(b));
        graph.connect(_cv(-b), _cv(a));
    }

    bool solve(vector<int>& result) {
        int i;
        vector<int> num(graph.n, -1), ord;
        ord.reserve(graph.n + 1);

        for (i = 0; i<graph.n; ++i) {
            _scc_dfs1(i, ord, num, i);
        }
        for (i = ord.size() - 1; 0 <= i; --i) {
            _scc_dfs2(ord[i], num, i + 1);
        }

        result.resize(n + 1);
        for (i = 1; i <= n; ++i) {
            if (num[i] == num[i + n])
                return false;
            result[i] = (num[i] < num[i + n]);
        }
        return true;
    }
};



int m, n, kei;

int lr[2020][2];

int main() {

    scanner >> n >> m;

    repeat(n) {
        scanner >> lr[cnt][0] >> lr[cnt][1];
        ++lr[cnt][0];
        ++lr[cnt][1];
    }

    sat_2 sat(n);

    for (int i = 0; i < n - 1; ++i) {
        int vl = m + 1 - lr[i][1];
        int vr = m + 1 - lr[i][0];
        for (int j = i + 1; j < n; ++j) {
            if ((lr[i][0] <= lr[j][0] && lr[i][1] >= lr[j][0]) ||
                (lr[i][0] <= lr[j][1] && lr[i][1] >= lr[j][1])) {
                sat.emplace((i + 1), -(j + 1));
                sat.emplace(-(i + 1), (j + 1));
            }
            if ((vl <= lr[j][0] && vr >= lr[j][0]) ||
                (vl <= lr[j][1] && vr >= lr[j][1])) {
                sat.emplace((i + 1), (j + 1));
                sat.emplace(-(i + 1), -(j + 1));
            }
        }
    }

    vector<int> result;
    if (sat.solve(result)) {
        cout << "YES" << endl;
    }
    else {
        cout << "NO" << endl;
    }

    return 0;
}