#include <stdio.h>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <list>
#include <queue>
#include <stack>
#include <cmath>
#include <ctime>
#include <cstdio>
#include <vector>
#include <string>
#include <bitset>
#include <cctype>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <numeric>
#include <complex>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <cassert>
#include <iostream>
#include <iterator>
#include <algorithm>
#include <functional>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vint;
typedef vector<vector<int>> v2int;
typedef vector<ll> vll;
typedef vector<vector<ll>> v2ll;
typedef list<int> liint;
typedef pair<int, int> pint;
const int INF = int(2e9);
const ll LINF = ll(2e9) * ll(2e9);
#define rep(i, n) REP(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define MSG(a) cout << #a << " " << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
template<class T, class C> void chmax(T& a, C b) { a > b ? : a = b; }
template<class T, class C> void chmin(T& a, C b) { a < b ? : a = b; }

int gcd(int a, int b) {
    int r = a % b;
    while (r != 0) {
        a = b;
        b = r;
        r = a % b;
    }
    return b;
}

int main() {
    int N;
    cin >> N;
    vint A(N);
    bool is_all_minus = true;
    bool is_all_plus = true;
    int first_minus_idx = -1;
    int first_plus_idx = -1;
    rep(i, N) {
        cin >> A[i];
        if (A[i] < 0) {
            is_all_plus = false;
            first_minus_idx = i;
        }
        if (A[i] >= 0) {
            is_all_minus = false;
            first_plus_idx = i;
        }
        if (A[i] == 0)
            first_plus_idx = i;
    }
    ll ans = 0;
    vector<pair<ll, ll>> ans_list(N);
    if (is_all_plus == true) {
        auto  minA_it = min_element(A.begin(), A.end());
        int minA_idx = distance(A.begin(), minA_it);
        int last_idx = 0;
        if (minA_idx == 0)
            last_idx = 1;
        ans = A[minA_idx];
        int j = 0;
        REP(i, 0, N) {
            if (i != minA_idx && i != last_idx) {
                ans_list[j] = make_pair(ans, A[i]);
                ans = ans - A[i];
                j++;
            }
        }
        ans_list[j] = make_pair(A[last_idx], ans);
        ans = A[last_idx] - ans;
    }
    else if (is_all_minus == true) {
        auto  maxA_it = max_element(A.begin(), A.end());
        int maxA_idx = distance(A.begin(), maxA_it);
        int last_idx = 0;
        if (maxA_idx == 0)
            last_idx = 1;
        ans = A[maxA_idx];
        int j = 0;
        REP(i, 0, N) {
            if (i != maxA_idx && i != last_idx) {
                ans_list[j] = make_pair(ans, A[i]);
                ans = ans - A[i];
                j++;
            }
        }
        ans_list[j] = make_pair(ans, A[last_idx]);
        ans = ans - A[last_idx] ;
    }
    else {
        ans = A[first_minus_idx];
        int j = 0;
        rep(i, N) {
            if (i != first_minus_idx && A[i] >= 0 && i != first_plus_idx) {
                ans_list[j] = make_pair(ans, A[i]);
                ans = ans - A[i];
                j++;
            }
        }
        ans_list[j] = make_pair(A[first_plus_idx], ans);
        ans = A[first_plus_idx] - ans;
        j++;
        rep(i, N) {
            if (A[i] < 0 && i != first_minus_idx) {
                ans_list[j] = make_pair(ans, A[i]);
                ans = ans - A[i];
                j++;
            }
        }
    }
    cout << ans << endl;
    rep(i, N - 1) {
        cout << ans_list[i].first << " " << ans_list[i].second << endl;
    }
    return 0;
}

Measured memory_bytes: 3840