#include<bits/stdc++.h>
// #include<atcoder/all>

using namespace std;
// using namespace atcoder;
using ll = long long;
using ull = unsigned long long;
using P = pair<int,int>;
#define rep(i,n) for(ll i = 0;i < (ll)n;i++)
#define ALL(x) (x).begin(),(x).end()
#define MOD 1000000007



int main(){
  
  int n;
  cin >> n;
  vector<ll> c(n);
  rep(i,n)cin >> c[i];
  ll res = -1ll*MOD*MOD;
  auto solve = [&](){
    ll a = 0,b = 0;
    for(int i = n-1;i >= 0;i-=2){
      a += c[i];
      if(i-1 >= 0)b += c[i-1];
    }
    ll k = abs(a)-abs(b);
    a = 0,b = 0;
    for(int i = n-1,j = 0;j <= i;i--,j++){
      a += c[i];
      if(i != j)b += c[j];
    }
    k = min(k,abs(a)-abs(b));
    res = max(res,k);
  };
  sort(ALL(c));
  solve();
  sort(ALL(c),greater<ll>());
  solve();
  cout << res << "\n";



  return 0;
}