#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=n-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define vtpl(x,y,z) vector<tuple<x,y,z>>
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={1,0,-1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}


struct SCC{
    int n;
    vector<vector<int>> g,rg;
    vector<int> vs,cmp;
    vector<bool> used;
    SCC(int _n){
        n=_n;
        g=vector<vector<int>>(n);rg=g;
        cmp=vector<int>(n);used=vector<bool>(n);
    }
    void add_edge(int f, int t){
        g[f].push_back(t);
        rg[t].push_back(f);
    }
    int init(){
        rep(i,n)if(!used[i])dfs(i);
        int k=0;
        used=vector<bool>(n,false);
        per(i,n){
            if(!used[vs[i]]){
                rdfs(vs[i],k);
                k++;
            }
        }
        return k;
    }
    private:
    void dfs(int v){
        used[v]=true;
        rep(i,g[v].size()){
            if(!used[g[v][i]])dfs(g[v][i]);
        }
        vs.push_back(v);
    }
    void rdfs(int v, int k){
        used[v]=true;cmp[v]=k;
        rep(i,rg[v].size()){
            if(!used[rg[v][i]]){
                rdfs(rg[v][i],k);
            }
        }
    }
};

struct twoSAT{
    vector<bool> ans;
    twoSAT(int _n):n(_n),graph(2*_n),ans(_n){}
    void add_edge(int i,bool x,int j,bool y){//i=>j;
        if(!x)i+=n;if(!y)j+=n;
        graph.add_edge((i+n)%(2*n),j);
        graph.add_edge((j+n)%(2*n),i);
    }
    bool exe(){
        graph.init();
        rep(i,n){
            if(graph.cmp[i]==graph.cmp[i+n])return false;
            else if(graph.cmp[i]>graph.cmp[i+n])ans[i]=true;
            else ans[i]=false;
        }
        return true;
    }
    private:
    int n;SCC graph;
};
bool cross(ll a,ll b,ll c,ll d){
    return (a<=d&&c<=b)||(c<=b&&a<=d);
}
int main(){
    ll n,m;cin >> n >>m;m--;
    twoSAT g(n);
    vl x(n),y(n);rep(i,n)cin >> x[i] >> y[i];
    rep(i,n){
        repl(j,i+1,n){
            if(cross(x[i],y[i],x[j],y[j])){
                g.add_edge(i,0,j,0);
            }
            if(cross(m-y[i],m-x[i],x[j],y[j])){
                g.add_edge(i,1,j,0);
            }
            if(cross(x[i],y[i],m-y[j],m-x[j])){
                g.add_edge(i,0,j,1);
            }
            if(cross(m-y[i],m-x[i],m-y[j],m-x[j])){
                g.add_edge(i,1,j,1);
            }
        }
    }

    if(g.exe()){
        cout << "YES" <<endl;
    }
    else{
        cout << "NO" <<endl;
    }
}