#include <bits/stdc++.h>
#include <time.h>
using namespace std;
 
#define sz(x) ((int)(x).size())
#define pb push_back
#define vt vector
#define arr array
#define fi first
#define se second
#define ends "\n"
#define sp ' '
#define fun function
#define rall(x) (x).rbegin(), (x).rend()
#define all(x) (x).begin(), (x).end()
 
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
 
const long long MOD=1e9+7; 
 
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) { cerr << to_string(h); if(sizeof...(t)) cerr << ", "; DBG(t...); }
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
 
const int LB = -2e9, RB = 2e9;
 
int main(void){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr); cerr.tie(nullptr);
 	
    int N, M; cin >> N >> M;
    vector<int> A(N); for(auto &a : A) cin >> a;
 
    queue<pair<int, int>> Q;
    set<int> st;
 
    for(auto &a : A){
    	Q.push({a, a});
    	st.insert(a);
    }
 
    vector<int> ans;
    int cnt = 0;
    ll sum = 0;
 
    while(cnt != M && !Q.empty()){
    	auto T = Q.front(); Q.pop();
    	if(T.fi - 1 >= LB){
    		if(st.find(T.fi - 1) == st.end()){
    			st.insert(T.fi - 1);
 
    			sum += (ll)abs((T.fi - 1) - T.se);
    			Q.push({T.fi - 1, T.se});
 
    			++cnt;
    			ans.pb(T.fi - 1);
 
    		}
    	}
 
    	if(T.fi + 1 <= RB){
    		if(st.find(T.fi + 1) == st.end()){
    			st.insert(T.fi + 1);
 
    			sum += (ll)abs((T.fi + 1) - T.se);
    			Q.push({T.fi + 1, T.se});
 
    			++cnt;
    			ans.pb(T.fi + 1);
    		}
    	}
    }
 
    cout << sum << ends;
    for(auto &a : ans)
    	cout << a << sp;
    cout << ends;
 	
}