include vector include algorithm include iostream include map using na

#include<vector>
#include<algorithm>
#include<iostream>
#include<map>

using namespace std;


int main()
{
	//freopen("input.txt", "r" , stdin);
	int n, s;
	cin >> n >> s;
	vector<int> V(n);
	for(int i = 0; i < n; i++)
		cin >> V[i];

	sort(V.begin(), V.end());
	int st = 0;
	vector<int> ans;
	int t = 0;
	for(int i = n-1; i >= 0; i--)
	{
		for( ; st < i && V[st] + V[i] <= s && st < n; st++) 
		{
			t = st;
		}

		

		if (st >= 0 && st < i && V[st] + V[i] > s)
		{
			ans.push_back(V[st]);
			ans.push_back(V[i]);
		}
		
		if(st >= i) break;
		st++;
 	}

	map<int, int> SS;
	map<int, int> B;
	for(int i = 0; i < ans.size(); i++)
		SS[ans[i]]++;
	
	for(int i = 0; i < n; i++)
		B[V[i]]++;
	sort(V.rbegin(), V.rend());
	for(int i = 0; i < n; i++)
	{
		if(SS[V[i]] < B[V[i]])
		{
			ans.push_back(V[i]);
			SS[V[i]]++;
		}
	}

	int aa = 0;
	int i = 0;
	for(; i < ans.size();)
	{
		if (i+1 < n && ans[i] + ans[i+1] <= s)
		{
			aa++;
			i += 2;
		}
		else
		{
			aa++;
			i++;
		}
	}

	cout << aa << endl;
	for(int i = 0; i < n; i++)
		cout << ans[i] << " ";
	
	cout << endl;
	return 0;
}