#include<bits/stdc++.h>
using namespace std;

#define int long long

typedef pair<int,int>pint;
typedef vector<int>vint;
typedef vector<pint>vpint;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
#define each(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++)
template<class T,class U>inline void chmin(T &t,U f){if(t>f)t=f;}
template<class T,class U>inline void chmax(T &t,U f){if(t<f)t=f;}

struct UF{
    int N;
    vint par;
    void init(int n){
        N=n;
        par.resize(N);
        rep(i,N)par[i]=i;
    }
    int find(int x){
        return x==par[x]?x:par[x]=find(par[x]);
    }
    void unite(int x,int y){
        par[find(y)]=find(x);
    }
    bool same(int x,int y){
        return find(x)==find(y);
    }
};

int N,M;
int x[114514],y[114514];

signed main(){
    cin>>N>>M;
    rep(i,N){
        cin>>x[i]>>y[i];
        x[i]--;y[i]--;
    }

    UF uf;uf.init(2*N);
    rep(i,N)rep(j,N)if(i!=j){
        if((x[i]<=x[j]&&x[j]<=y[i])||(x[i]<=y[j]&&y[j]<=y[i]))uf.unite(i,j+N);
        int xx=M-1-x[j],yy=M-1-y[j];
        if((x[i]<=xx&&xx<=y[i])||(x[i]<=yy&&yy<=y[i]))uf.unite(i,j);
    }

    rep(i,N)if(uf.same(i,i+N)){
        cout<<"NO"<<endl;
        return 0;
    }
    cout<<"YES"<<endl;
    return 0;
}