// template version 1.12
using namespace std;
#include <iostream>
#include <bits/stdc++.h>

// varibable settings
#define infile "../test/sample-1.in"
#define int long long //{{{
const int INF=1e18;
const int MOD=1e9+7; //}}}

// define basic macro {{{
#define _overload3(_1,_2,_3,name,...) name
#define _rep(i,n) repi(i,0,n)
#define repi(i,a,b) for(int i=(int)(a);i<(int)(b);++i)
#define rep(...) _overload3(__VA_ARGS__,repi,_rep,)(__VA_ARGS__)
#define _rrep(i,n) rrepi(i,0,n)
#define rrepi(i,a,b) for(int i=(int)((b)-1);i>=(int)(a);--i)
#define rrep(...) _overload3(__VA_ARGS__,rrepi,_rrep,)(__VA_ARGS__)
#define each(i,a) for (auto&& i : a)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define pb(a) push_back(a)
#define mp(a, b) make_pair(a, b)
#define uni(x) sort(all(x));x.erase(unique(all(x)),x.end())
#define ub upper_bound
#define lb lower_bound
#define posl(A, x) (lower_bound(all(A), x)-A.begin())
#define posu(A, x) (upper_bound(all(A),x)-A.begin())
template<class T> inline void chmax(T &a, const T &b) { if((a) < (b)) (a) = (b); }
template<class T> inline void chmin(T &a, const T &b) { if((a) > (b)) (a) = (b); }

typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef long double ld;
typedef pair<int,int> pii;
typedef tuple<int,int,int> iii;

template<typename T> using PQ = priority_queue<T, vector<T>, greater<T>>;
struct Fast { Fast(){ std::cin.tie(0); ios::sync_with_stdio(false); } } fast;

#if defined(PCM) || defined(LOCAL)
  #include "lib/dump.hpp"
#else
  #define dump(...) 42
  #define dump_1d(...) 42
  #define dump_2d(...) 42
#endif
//}}}

int solve(){
  int n;cin>>n;
  vector<int> a(n);
  int p=0;int q=0;
  int last=-1;
  rep(i, n) {
    cin>>a[i];
    if (a[i]>0) p++;
    if (a[i]<0){
      q++;
    }
  }

  sort(all(a));
  dump(a);

  rep(i,n) {
    if(a[i]<0) last = i;
  }
  dump(last);
  if (n==2){
  }

  vector<pair<int, int>> ans;
  int M = 0;
  if (p>0 and q>0){
    if (n==2) {
      M = a[1]-a[0];
      cout << M << endl;
      cout << a[1] << " " << a[0] << endl;
      return 0;
    }

    // assert(false);
    M = a[n-1];
    rep(i, 0, n-2){
      if (i<last){
        ans.pb(mp(M, a[i]));
        M -= a[i];
      }
      else if (i==last){
        ans.pb(mp(a[i], M));
        M = a[i]-M;
      }
      else if (i>last){
        ans.pb(mp(M, a[i]));
        M = M-a[i];
      }
    }

    //n-1
    if (a[n-2]<0){
      ans.pb(mp(M, a[n-2]));
      M = M-a[n-2];
    }
    else{
      ans.pb(mp(a[n-2],M));
      M = a[n-2]-M;
    }
  }
  else if (q==0){
    if (n==2) {
      M = a[1]-a[0];
      cout << M << endl;
      cout << a[1] << " " << a[0] << endl;
      return 0;
    }
    M = a[0] - a[1];
    ans.pb(mp(a[0], a[1]));
    rep(i, 2, n-1){
      ans.pb(mp(M, a[i]));
      M -= a[i];
    }
    ans.pb(mp(a[n-1], M));
    M = a[n-1] - M;
  }
  else if (q>0){
    if (n==2) {
      M = a[1]-a[0];
      cout << M << endl;
      cout << a[1] << " " << a[0] << endl;
      return 0;
    }
    M = a[n-1] - a[n-2];  //>0
    ans.pb(mp(a[n-1], a[n-2]));
    rep(i, 1, n-2){
      ans.pb(mp(M, a[i]));
      M -= a[i];
    }
    ans.pb(mp(M, a[0]));
    M = M - a[0];
  }

  cout << M << endl;
  rep(i, sz(ans)){
    int x,y;
    tie(x,y)=ans[i];
    cout << x << " " << y << endl;
  }
    
  return 0;
}

signed main() { //{{{
#ifdef INPUT_FROM_FILE
  std::ifstream in(infile);
  std::cin.rdbuf(in.rdbuf());
#endif
  solve();
  return 0;
} //}}}


Measured memory_bytes: 4336