#include <vector>
#include <list>
#include <map>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <queue>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <fstream>
#include <cstdio>
#include <climits>
#include <complex>
#include <cstdint>
#include <tuple>

#define M_PI       3.14159265358979323846

using namespace std;

//conversion
//------------------------------------------
inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v; }
template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str(); }
inline int readInt() { int x; scanf("%d", &x); return x; }

//typedef
//------------------------------------------
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef pair<int, PII> TIII;
typedef long long LL;
typedef unsigned long long ULL;
typedef vector<LL> VLL;
typedef vector<VLL> VVLL;

//container util

//------------------------------------------
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define SQ(a) ((a)*(a))
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())

//repetition
//------------------------------------------
#define FOR(i,s,n) for(int i=s;i<(int)n;++i)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define trav(a, x) for(auto& a : x)
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x).size()
struct Edge {
    int to, cost;
    Edge(int to, int cost): to(to), cost(cost) {}
};

typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vector<Edge>> AdjList;
AdjList graph;

const int INF = 100000000;

int N, M;

vector<LL> v1, v2;
int main() {
    //cout << fixed << setprecision(15);

    int N; cin >> N;
    REP(i, N){
        LL a = readInt();
        if(a > 0) v1.push_back(a);
        else v2.push_back(a);
    }

    LL n = v1.size();
    LL m = v2.size();

    if(n==0){
        sort(v2.begin(), v2.end(), greater<LL>());
        vector<pair<LL, LL>> vp;
        LL t = v2[0];
        for(int i=1; i<m; ++i){
            vp.push_back({t, v2[i]});
            t -= v2[i];
        }

        cout << t << endl;
        for(auto e: vp){
            cout << e.first << " " << e.second << endl;
        }
    }else if(m==0){
        sort(v1.begin(), v1.end(), greater<LL>());

        if(n == 1){
            cout << v1[0] << endl;
        }else if(n==2){
            cout << v1[1]-v1[0] << endl;
        }else{
            vector<pair<LL, LL>> vp;
            LL t = v1[0];

            vp.push_back({v1[n-1], t});
            v1[n-1] -= t;
            t = v1[n-1];
            for(int i=n-2; i>=2; --i){
                vp.push_back({t, v1[i]});
                t -= v1[i];
            }

            vp.push_back({v1[1], t});
            t = v1[1]-t;
            cout << t << endl;
            for(auto e: vp){
                cout << e.first << " " << e.second << endl;
            }
        }
    }
    else{
        int idx = 0;
        int t = v2[0];
        vector<pair<int, int>> vp;
        for(int i=0; i<n-1; ++i){
            vp.push_back({t, v1[i]});
            t -= v1[i];
        }
        v2[0] = t;
        t = v1[n-1];
        for(int i=0; i<m; ++i){
            vp.push_back({t, v2[i]});
            t -= v2[i];
        }
        cout << t << endl;
        for(auto e: vp){
            cout << e.first << " " << e.second << endl;
        }
    }

    return 0;
}

Measured memory_bytes: 4340