#include<iostream> #include<set> #include<algorithm> #include<vector> #include<string> #include<set> #include<map> #include<numeric> #include<queue> #include<cmath> #include <unordered_set> #include<cassert> using namespace std; typedef long long ll; const ll INF=1LL<<60; typedef pair<ll,int> P; typedef pair<int,P> PP; const ll MOD=1e9+7; int main(){ int N; cin>>N; vector<ll> c(N); for(int i=0;i<N;i++){ cin>>c[i]; } ll ans=-INF; sort(c.begin(),c.end()); for(int t=0;t<2;t++){ vector<ll> sum(2,0); for(int i=0;i<N;i++){ sum[i%2]+=c[i]; } //ll d=sum[0] - sum[1];//abs(sum[0]) - abs(sum[1]); ll d=abs(sum[0]) - abs(sum[1]); ans=max(ans,d); reverse(c.begin(),c.end()); } cout<<ans<<endl; }