#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T>
ostream_iterator<T> oit(const string &s = " "){ return ostream_iterator<T>(cout,s.c_str()); }
inline auto rep(int l, int r) { return views::iota(min(l, r), r); }
inline auto rep(int n) { return rep(0, n); }
inline auto rep1(int l, int r) { return rep(l, r + 1); }
inline auto rep1(int n) { return rep(1, n + 1); }
inline auto per(int l, int r) { return rep(l, r) | views::reverse; }
inline auto per(int n) { return per(0, n); }
inline auto per1(int l, int r) { return per(l, r + 1); }
inline auto per1(int n) { return per(1, n + 1); }
#define A(a) begin(a),end(a)
inline auto len = ranges::ssize;

struct chash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};
template<typename T, typename U> using pb_map = gp_hash_table<T, U, chash>;
template<typename T> using pb_set = gp_hash_table<T, null_type, chash>;
#define K first
#define V second

using ll = long long;
using ld = long double;

using vi = vector<int>;
using vii = vector<vector<int>>;
typedef vector<ll> vll;
using pll = pair<ll,ll>;
using pii = pair<int,int>;

void run()
{
    ll n,R; cin >> n >> R;
    vll ans;
    vll v(n);for(ll &x : v) cin >> x;

    while(not v.empty()){
        ranges::sort(v);
        pll here {-1,0};
        for(int i : rep(len(v))){ //try backwords and forwards
            {//forwards
                auto lb = ranges::lower_bound(v,v[i]+2*R);
                ll place = v[i]+R;
                ll cnt = lb-(i+v.begin());
                if(cnt==here.second and place<here.first) here={place,cnt}; 
                else if(cnt>here.second) here = {place,cnt};
            }
            { //backwords
                auto lb = ranges::lower_bound(v,v[i]-2*R);
                ll place = v[i]-R;
                ll cnt = (i+v.begin())-lb+1;
                if(cnt==here.second and place<here.first) here={place,cnt}; 
                else if(cnt>here.second) here = {place,cnt};
            }
        }

        ll place = here.first;
        // cout << here.first << " " << here.second << endl;
        ans.push_back(place);
        erase_if(v,[&](ll x){ return abs(place-x)<=R;}); //kill it all!!!
    }

    cout << len(ans) << '\n';
    ranges::copy(ans,oit<ll>()),cout << '\n';
}

int main()
{
    //KING OF THE WORLD...... U.W.T.B
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    run();
}