#include <bits/stdc++.h>
#include <random>

using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef double ld;
#define int ll
typedef vector<char> vc;
typedef vector<vc> vvc;
typedef vector<vvc> vvvc;
typedef pair<int, int> pii;
typedef pair<pii, pii> piii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vpi;
typedef vector< vi > vvi;
typedef vector< vvi > vvvi;
typedef vector<short> vs;
typedef vector<vs> vvs;
typedef vector<vvs> vvvs;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<ld> vld;
typedef vector<vld> vvld;
typedef vector<vvld> vvvld;
typedef vector<string> vst;
typedef vector<vst> vvst;
typedef pair<ld, ld> pld;

#define inmin(a, b) a = min(a, (b))
#define inmax(a, b) a = max(a, (b))
#define ALL(a) a.begin(),a.end()
#define RALL(a) a.rbegin(),a.rend()
#define sqr(x) ((x) * (x))
#define fori(i, n) for(int i = 0; i < int(n); ++i)
#define SZ(a) ((int)((a).size()))
#define triple(T) tuple<T, T, T>
#define quad(T) tuple<T, T, T, T>
#define watch(x) cerr << (#x) << " = " << (x) << endl;

#ifdef RUS_HOME
#define cerr cout
#else
#define cerr if (false) cerr
#endif

const double PI = 2 * acos(0.0);
#define rand shittttty_shit
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng_64(chrono::steady_clock::now().time_since_epoch().count());

const string DIGITS = "0123456789";
const string ALPH = "abcdefghijklmnopqrstuvwxyz";


template <class T0, class T1>
inline ostream & operator << (ostream &out, pair<T0, T1> &a) {
    return out << "{" << a.first << ", " << a.second << "}";
}

template <class T0, class T1>
inline istream & operator >> (istream &in, pair<T0, T1> &a) {
    return in >> a.first >> a.second;
}

template <class T0, class T1, class T2>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) << ", " << get<2>(a) << "}";
}

template <class T0, class T1, class T2, class T3>
inline ostream & operator << (ostream &out, tuple<T0, T1, T2, T3> &a) {
    return out << "{" << get<0>(a) << ", " << get<1>(a) << ", " << get<2>(a) << ", " <<  get<3>(a) << "}";
}

template<class T>
inline ostream & operator << (ostream &out, vector<T> &a) {
    out << "[";
    fori (i, a.size())
        out << a[i] << vector<string>{", ", "]  "}[i + 1 == a.size()];
    return out;
}


void smain();



signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
#ifdef RUS_HOME
    freopen("input", "r", stdin);
    clock_t start = clock();
#endif
    cout << setprecision(12) << fixed;
    smain();
#ifdef RUS_HOME
    cout << "\n\n\n\nTOTAL EXECUTION TIME: " << float( clock () - start ) /  CLOCKS_PER_SEC << endl;
#endif
    return 0;
}

const int MOD=998244353,N=1e5+100,oo=1e15;


void smain() {

    int n;
    cin>>n;
    vi a(n);
    int cnt=0;
    multiset<int>s,t;

    for(int i=0;i<n;i++){
        cin>>a[i];
        if(a[i]>0)
            s.insert(a[i]);
        else if(a[i]<0)
            t.insert(a[i]);
        else
            cnt++;
    }

    if(n==2){
        sort(ALL(a));
        cout<<a[1]-a[0]<<"\n"<<a[1]<<" "<<a[0];
        return;
    }

    vpi ans;
    if(SZ(s)==0){
        if(cnt){
            cnt--;
            s.insert(0);
        }else{
            auto it=t.end(); it--;
            int u=*it;
            t.erase(it);
            it=t.end(); it--;
            int v=*it;
            t.erase(it);
            s.insert({u-v});
            ans.push_back({u,v});
        }
    }
    if(SZ(t)==0){
        if(cnt){
            cnt--;
            t.insert(0);
        }else{
            auto it=s.begin();
            int u=*it;
            s.erase(it);
            it=s.begin();
            int v=*it;
            s.erase(it);
            t.insert({u-v});
            ans.push_back({u,v});
        }
    }

    for(int i=0;i<cnt;i++){
        s.insert(0);
    }

    while(SZ(s)>1){
        auto it=t.begin();
        int u=*it;
        t.erase(it);
        it=s.begin();
        int v=*it;
        s.erase(it);
        t.insert(u-v);
        ans.push_back({u,v});
    }

    while(SZ(t)>1){
        auto it=t.end(); it--;
        int u=*it;
        t.erase(it);
        it=s.end(); it--;
        int v=*it;
        s.erase(it);
        s.insert(v-u);
        ans.push_back({v,u});
    }

    auto it=s.begin();
    int u=*it;
    it=t.begin();
    int v=*it;
    ans.push_back({u,v});
    cout<<u-v<<"\n";
    for(auto p:ans){
        cout<<p.first<<" "<<p.second<<"\n";
    }





}

Measured memory_bytes: 10864