#ifndef _GLIBCXX_NO_ASSERT
#include <cassert>
#endif
#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>

#if __cplusplus >= 201103L
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
#endif

// C++
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>

#if __cplusplus >= 201103L
#include <array>
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <forward_list>
#include <future>
#include <initializer_list>
#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <scoped_allocator>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#endif

using namespace std;

#define rep(i, n) for(ll i = 0; i < n; i++)
#define revrep(i, n) for(ll i = n-1; i >= 0; i--)
typedef long long ll;
typedef pair<int,int> Pint;
typedef pair<ll, ll> P;
typedef vector<ll> vec;
typedef vector<vec> mat;
//typedef pair<int, pair<int, int>> P;
//typedef tuple<int,int,int> T;
ll INFL = 1000000000000000010;//10^18 = 2^60
int INF = 1000000000;//10^9
ll MOD  = 1000000007;
//vector<int> dy = {0,0,1,-1};
//vector<int> dx = {1,-1,0,0};

int main(void){
  ll N;
  cin >> N;
  vector<ll> A(N);
  rep(i, N) cin >> A[i];

  sort(A.begin(), A.end());
  reverse(A.begin(), A.end());
  if(N == 2){
    if(A[0] < 0){
      cout << A[1] - A[0] << endl;
      cout << A[1] << " " << A[0] << endl;
    }else{
      cout << A[0] - A[1] << endl;
      cout << A[0] << " " << A[1] << endl;
    }
    return 0;
  }
  ll ans = 0;
  rep(i, N){
    if(i == N-1){
      ans += -1 * A[i];
    }else{
      ans += abs(A[i]);
    }
  }
  if(A[0] < 0){
    ans = 0;
    for(int i = 0; i < N; i++){
      if(i == 0){
        ans += A[i];
      }else{
        ans -= A[i];
      }
    }
  }
  cout << ans << endl;

  if(A[0] <= 0){
    ll sum = A[0] - A[1];
    cout << A[0] << " " << A[1] << endl;
    for(int i = 2; i < N; i++){
      cout << sum << " " << A[i] << endl;
      sum = sum - A[i];
    }
  }else if(A[N-1] >= 0){
    ll sum = A[N-1] - A[N-2];
    cout << A[N-1] << " " << A[N-2] << endl;
    for(int i = N-3; i >= 1; i--){
      cout << sum << " " << A[i] << endl;
      sum -= A[i];
    }
    cout << A[0] << " " << sum << endl;
  }else{
    if(A[1] >= 0){
      ll sum = A[N-1] - A[0];
      cout << A[N-1] << " " << A[0] << endl;
      bool xx = 1;
      for(int i = 1; i < N-1; i++){
        if(xx && A[i+1] < 0){
          xx = 0;
          cout << A[i] << " " << sum << endl;
          sum = A[i] - sum;
        }else{
          cout << sum << " " << A[i] << endl;
          sum -= A[i];
          }
        }
      }else{
        ll sum = A[0] - A[1];
        cout << A[0] << " " << A[1] << endl;
        for(int i = 2; i < N; i++){
          cout << sum << " " << A[i] << endl;
          sum -= A[i];
        }
      }
    }
}


Measured memory_bytes: 2688