#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define ll long long int
#define ull unsigned long long int
#define f(a,b) for(ll i=a;i<b;i++)
#define f1(a,b) for(ll i=a;i<=b;i++)
#define fd(a,b) for(ll i=a;i>=b;i--)
#define fj(j,a,b) for(ll j=a;j<b;j++)
#define fk(k,a,b) for(ll k=a;k<b;k++)
#define fat(m) for(auto it:m)
ll power(ll x,ll y,ll p){ll res=1;x=x%p;while(y>0){if(y&1)res=((res%p)*(x%p))%p;y=y>>1;x=(x*x)%p;}return res;}
ll pow1(ll x,ll y){ll res=1;while(y>0){if(y&1)res=(res*x);y=y>>1;x=x*x;}return res;}
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
#define vp vector<pair<int,int>>
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(),v.end()
#define alld(v) v.begin(),v.end(),greater<int>()
#define sz(v) v.size()
#define endl "\n"
#define ff first
#define ss second
const ll N=1e5+1;

void solve()
{
    ll n,m,k,p=0,q=0,s=0,c=0,i,j;
    cin>>n;
    ll a[n]={0};
    if(n==1)
    {
        cin>>a[0];
        cout<<a[0];
        return;
    }
    c=1e18;
    f(0,n)
    {
        cin>>a[i];
        if(a[i]<=0)
            p++;
        if(a[i]>=0)
            q++;
        c=min(a[i],c);
        s+=llabs(a[i]);
    }
    cout<<c<<" "<<s<<endl;
    cout<<p<<" "<<q<<endl;
    if(p&&q)
    {
        cout<<s;
        return;
    }
    cout<<s-2*c;

    return;
}

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "rt", stdin);
        freopen("output.txt", "wt", stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t=1;
  //  cin>>t;
    while(t--)
    {
        solve();
    }
    #ifndef ONLINE_JUDGE
        cout<<"\nTime Elapsed: "<<1000*(long double)clock()/(long double)CLOCKS_PER_SEC<<"ms\n";
    #endif
    return 0;
}


#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define ll long long int
#define ull unsigned long long int
#define f(a,b) for(ll i=a;i<b;i++)
#define f1(a,b) for(ll i=a;i<=b;i++)
#define fd(a,b) for(ll i=a;i>=b;i--)
#define fj(j,a,b) for(ll j=a;j<b;j++)
#define fk(k,a,b) for(ll k=a;k<b;k++)
#define fat(m) for(auto it:m)
ll power(ll x,ll y,ll p){ll res=1;x=x%p;while(y>0){if(y&1)res=((res%p)*(x%p))%p;y=y>>1;x=(x*x)%p;}return res;}
ll pow1(ll x,ll y){ll res=1;while(y>0){if(y&1)res=(res*x);y=y>>1;x=x*x;}return res;}
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
#define vp vector<pair<int,int>>
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(),v.end()
#define alld(v) v.begin(),v.end(),greater<int>()
#define sz(v) v.size()
#define endl "\n"
#define ff first
#define ss second
const ll N=1e5+1;

void solve()
{
    ll n,m,k,p=0,q=0,s=0,c=0,i,j;
    cin>>n;
    ll a[n]={0};
    if(n==1)
    {
        cin>>a[0];
        cout<<a[0];
        return;
    }
    c=1e18;
    f(0,n)
    {
        cin>>a[i];
        if(a[i]<=0)
            p++;
        if(a[i]>=0)
            q++;
        c=min(a[i],c);
        s+=llabs(a[i]);
    }
  //  cout<<c<<" "<<s<<endl;
    //cout<<p<<" "<<q<<endl;
    if(p&&q)
    {
        cout<<s;
        return;
    }
    cout<<s-2*c;

    return;
}

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "rt", stdin);
        freopen("output.txt", "wt", stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t=1;
  //  cin>>t;
    while(t--)
    {
        solve();
    }
    #ifndef ONLINE_JUDGE
        cout<<"\nTime Elapsed: "<<1000*(long double)clock()/(long double)CLOCKS_PER_SEC<<"ms\n";
    #endif
    return 0;
}


#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define ll long long int
#define ull unsigned long long int
#define f(a,b) for(ll i=a;i<b;i++)
#define f1(a,b) for(ll i=a;i<=b;i++)
#define fd(a,b) for(ll i=a;i>=b;i--)
#define fj(j,a,b) for(ll j=a;j<b;j++)
#define fk(k,a,b) for(ll k=a;k<b;k++)
#define fat(m) for(auto it:m)
ll power(ll x,ll y,ll p){ll res=1;x=x%p;while(y>0){if(y&1)res=((res%p)*(x%p))%p;y=y>>1;x=(x*x)%p;}return res;}
ll pow1(ll x,ll y){ll res=1;while(y>0){if(y&1)res=(res*x);y=y>>1;x=x*x;}return res;}
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
#define vp vector<pair<int,int>>
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(),v.end()
#define alld(v) v.begin(),v.end(),greater<int>()
#define sz(v) v.size()
#define endl "\n"
#define ff first
#define ss second
const ll N=1e5+1;

void solve()
{
    ll n,m,k,p=0,q=0,s=0,c=0,i,j;
    cin>>n;
    ll a[n]={0};
    ll c1=1e18,c2=c1;
    f(0,n)
    {
        cin>>a[i];
        if(a[i]<0)
            p++,
            c1=min(a[i],c1);
        else
            q++,
            c2=min(a[i],c2);
        s+=llabs(a[i]-0LL);
    }
    if(n==1)
    {
        cout<<a[0];
        return;
    }
    if(p&&q)
    {
        cout<<s;
        return;
    }
    if(p==0)
        cout<<s-2*c2;
    else cout<<s-2*c1;

    return;
}

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "rt", stdin);
        freopen("output.txt", "wt", stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t=1;
  //  cin>>t;
    while(t--)
    {
        solve();
    }
    #ifndef ONLINE_JUDGE
        cout<<"\nTime Elapsed: "<<1000*(long double)clock()/(long double)CLOCKS_PER_SEC<<"ms\n";
    #endif
    return 0;
}


#include<bits/stdc++.h>
using namespace std;
#define mod 1000000007
#define ll long long int
#define ull unsigned long long int
#define f(a,b) for(ll i=a;i<b;i++)
#define f1(a,b) for(ll i=a;i<=b;i++)
#define fd(a,b) for(ll i=a;i>=b;i--)
#define fj(j,a,b) for(ll j=a;j<b;j++)
#define fk(k,a,b) for(ll k=a;k<b;k++)
#define fat(m) for(auto it:m)
ll power(ll x,ll y,ll p){ll res=1;x=x%p;while(y>0){if(y&1)res=((res%p)*(x%p))%p;y=y>>1;x=(x*x)%p;}return res;}
ll pow1(ll x,ll y){ll res=1;while(y>0){if(y&1)res=(res*x);y=y>>1;x=x*x;}return res;}
#define vi vector<int>
#define vll vector<ll>
#define vvi vector<vector<int>>
#define vvll vector<vector<ll>>
#define vp vector<pair<int,int>>
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(),v.end()
#define alld(v) v.begin(),v.end(),greater<int>()
#define sz(v) v.size()
#define endl "\n"
#define ff first
#define ss second
const ll N=1e5+1;

void solve()
{
    ll n,m,k,p=0,q=0,s=0,c=0,i,j;
    cin>>n;
    ll a[n]={0};
    if(n==1)
    {
        cin>>a[0];
        cout<<a[0];
        return;
    }
    ll c1=1e18,c2=c1;
    f(0,n)
    {
        cin>>a[i];
        if(a[i]<=0)
            p++,
            c1=min(a[i],c1);
        if(a[i]>=0)
            q++,
            c2=min(a[i],c2);

        s+=llabs(a[i]);
    }
  //  cout<<c<<" "<<s<<endl;
    //cout<<p<<" "<<q<<endl;
    if(p&&q)
    {
        cout<<s;
        return;
    }
    if(p==0)
        cout<<s-2*llabs(c2);
    else cout<<s-2*llabs(c1);

    return;
}

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "rt", stdin);
        freopen("output.txt", "wt", stdout);
    #endif
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    int t=1;
  //  cin>>t;
    while(t--)
    {
        solve();
    }
    #ifndef ONLINE_JUDGE
        cout<<"\nTime Elapsed: "<<1000*(long double)clock()/(long double)CLOCKS_PER_SEC<<"ms\n";
    #endif
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    bool x, y;
    x = y = false;
    long long sum = 0;
    int mn = 1e9;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        mn = min(mn,abs(a));
        if (a >= 0) {
            x = true;
        }
        if (a <= 0) {
            y = true;
        }
        sum += abs(a);
    }
    if (x && y) {
        cout << sum;
    } else {
        cout << sum-mn*2;
    }
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    if (n == 1) {
        int a;
        cin >> a;
        cout << a;
        return 0;
    }
    bool x, y;
    x = y = false;
    long long sum = 0;
    int mn = 1e9;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        mn = min(mn,abs(a));
        if (a >= 0) {
            x = true;
        }
        if (a <= 0) {
            y = true;
        }
        sum += abs(a);
    }
    if (x && y) {
        cout << sum;
    } else {
        cout << sum-mn*2;
    }
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n, mn, mx;
    cin >> n >> mx;
    for (int i = 1; i < n; i++) {
        int a;
        cin >> a;
        mx = max(abs(a-mx),abs(a+mx));
    }
    cout << mx;
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n;
    cin >> n;
    if (n == 1) {
        int a;
        cin >> a;
        cout << a;
        return 0;
    }
    bool x, y;
    x = y = false;
    long long sum = 0;
    int mn = 1e9;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        mn = min(mn,abs(a));
        if (a >= 0) {
            x = true;
        }
        if (a <= 0) {
            y = true;
        }
        sum += abs(a);
    }
    if (x && y) {
        cout << sum;
    } else {
        cout << sum-mn*2;
    }
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    long long mn, mx;
    cin >> n >> mx;
    mn = mx;
    for (int i = 1; i < n; i++) {
        int a;
        cin >> a;
        mx = max(abs(a-mx),abs(a-mn));
        mn = -mx;
    }
    cout << mx;
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    long long sum = 0;
    int p = -1;
    vector<long long> v;
    for (int i = 0; i < n; i++) {
        long long a;
        cin >> a;
        if (a >= 0) {
            p = v.size();
            a -= sum;
            v.push_back(a);
            sum = 0;
        }
        if (a < 0) {
            sum += a;
        }
    }
    if (p != -1) {
        v[p] -= sum;
    }
    if (v.size() == 1) {
        cout << v[0];
        return 0;
    }
    long long mx = abs(v[0]-v[1]), mn = -mx;
    for (int i = 2; i < v.size(); i++) {
        mx = max(abs(v[i]-mx),abs(v[i]-mn));
        mn = -mx;
    }
    cout << mx;
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n, mn, mx;
    cin >> n >> mx;
    mn = mx;
    for (int i = 1; i < n; i++) {
        int a;
        cin >> a;
        mx = max(abs(a-mx),abs(a-mn));
        mn = -mx;
    }
    cout << mx;
    return 0;
}


#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    if (n == 1) {
        int a;
        cin >> a;
        cout << a;
        return 0;
    }
    bool x, y;
    x = y = false;
    long long sum = 0;
    int mn = 1e9;
    for (int i = 0; i < n; i++) {
        int a;
        scanf("%d", &a);
        mn = min(mn,abs(a));
        if (a >= 0) {
            x = true;
        }
        if (a <= 0) {
            y = true;
        }
        sum += abs(a);
    }
    if (x && y) {
        cout << sum;
    } else {
        cout << sum-mn*2;
    }
    return 0;
}


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                                                                  .:J: :;  .,:K6BQS7:.,.,.
                                                                    :r7Ji;r7;::;;.
                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans, flag, l1, l2;
        flag = ans = l1 = l2 = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] > 0)
                l1++;
            if(lps[i] < 0)
                l2++;
            if(lps[i] == 0)
                flag = 1;
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        if(flag == 1)
        {
            printf("%lld\n", ans);
            continue;
        }
        if(n == 2)
        {
            printf("%lld\n", abs(lps[1] - lps[2]));
            continue;
        }
        if(l1 == n || l2 == n)
        {
            int s = lps[1];
            for(int i=2; i<=n; i++)
            {
                if(lps[i] != lps[i-1])
                {
                    s = min(s, abs(lps[i] - lps[i-1]));
                }
            }
            printf("%lld\n", ans -= s * 2);
        }
        else
            printf("%lld\n", ans);
    }
    return 0;
}

/*

*/


/**

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                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans = 0;
        int flag = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] == 0)
                flag = 1;
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        if(flag == 1)
        {
            printf("%lld\n", ans);
            continue;
        }
        if(n == 2)
        {
            printf("%lld\n", abs(lps[1] - lps[2]));
            continue;
        }
        int s = lps[1];
        for(int i=2; i<=n; i++)
        {
            if(lps[i] != lps[i-1])
            {
                s = min(s, abs(lps[i] - lps[i-1]));
            }
        }
        printf("%lld\n", ans -= s * 2);
    }
    return 0;
}

/*

*/


/**

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                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        int s = lps[1];
        for(int i=2; i<=n; i++)
        {
            if(lps[i] != lps[i-1])
            {
                s = min(s, abs(lps[i] - lps[i-1]));
            }
        }
        printf("%lld\n", ans -= s * 2);
    }
    return 0;
}

/*

*/


/**

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                                                                    :r7Ji;r7;::;;.
                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        if(n == 2)
        {
            printf("%lld\n", abs(lps[1] - lps[2]));
            continue;
        }
        int s = lps[1];
        for(int i=2; i<=n; i++)
        {
            if(lps[i] != lps[i-1])
            {
                s = min(s, abs(lps[i] - lps[i-1]));
            }
        }
        printf("%lld\n", ans -= s * 2);
    }
    return 0;
}

/*

*/


/**

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                                                                  .:J: :;  .,:K6BQS7:.,.,.
                                                                    :r7Ji;r7;::;;.
                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans, flag, l1, l2;
        flag = ans = l1 = l2 = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] > 0)
                l1++;
            if(lps[i] < 0)
                l2++;
            if(lps[i] == 0)
                flag = 1;
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        sort(lps+1, lps+1+n);
        if(flag == 1)
        {
            printf("%lld\n", ans);
            continue;
        }
        if(n == 2)
        {
            printf("%lld\n", abs(lps[1] - lps[2]));
            continue;
        }
        if(l1 == n || l2 == n)
        {
            int s = lps[1];
            for(int i=2; i<n; i++)
            {
                s -= lps[i];
            }
            lps[n] -= s;
            printf("%lld\n", lps[n]);
        }
        else
            printf("%lld\n", ans);
    }
    return 0;
}

/*

*/


#include <iostream>
#include <stdio.h>
#include <string>
#include <string.h>
#include <math.h>
#include <algorithm>
using namespace std;
#define ll long long
ll num[501000];
int main()
{
    ll sum;
    ll n,i,x=0,y=0,z=0;
    double minn;
    cin>>n;
    cin>>num[0];
    minn=fabs(num[0]);
    sum=fabs(num[0]);
    if(num[0]<0)
        x=1;
    if(num[0]>0)
        y=1;
    if(num[0]==0)
        z=1;
    for(i=1;i<n;i++)
    {
        cin>>num[i];
        sum+=fabs(num[i]);
        if(minn>fabs(num[i]))
            minn=fabs(num[i]);
        if(num[i]<0)
            x=1;
        if(num[i]>0)
            y=1;
        if(num[i]==0)
            z=1;
    }
    if(n==1)
        cout<<num[0]<<endl;
    else
    {
        if(z||(x&&y))
            cout<<sum<<endl;
        else
            cout<<sum-minn*2<<endl;
    }
    return 0;
}


/**

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                                                                  .:J: :;  .,:K6BQS7:.,.,.
                                                                    :r7Ji;r7;::;;.
                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
char str[maxn];
int lps[maxn];
int lpa[maxn];
bool cmp(int a, int b)
{
    return a > b;
}
signed main()
{
    int n;
    while(~scanf("%lld", &n))
    {
        int ans, flag, l1, l2;
        flag = ans = l1 = l2 = 0;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] > 0)
                l1++;
            if(lps[i] < 0)
                l2++;
            if(lps[i] == 0)
                flag = 1;
            if(lps[i] < 0)
                ans -= lps[i];
            else
                ans += lps[i];
        }
        sort(lps+1, lps+1+n);
        if(flag == 1)
        {
            printf("%lld\n", ans);
            continue;
        }
        if(n == 1)
        {
            printf("%lld\n", lps[1]);
            continue;
        }
        if(l1 == n || l2 == n)
        {
            int s = lps[1];
            for(int i=2; i<n; i++)
            {
                s -= lps[i];
            }
            lps[n] -= s;
            printf("%lld\n", abs(lps[n]));
        }
        else
            printf("%lld\n", abs(ans));
    }
    return 0;
}

/*

*/


/**

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                                                                    :r7Ji;r7;::;;.
                                                                        .                                                                             **/

#include <bits/stdc++.h>
#define int long long
using namespace std;
const int maxn = 1e6+5;
int lps[maxn];
bool cmp(int x, int y)
{
    return x > y;
}
signed main()
{
    int n, flag, l1, l2, ans;
    while(~scanf("%lld", &n))
    {
        l1 = l2 = flag = ans = 0;
        int in = 1e9;
        for(int i=1; i<=n; i++)
        {
            scanf("%lld", &lps[i]);
            if(lps[i] == 0) flag = 1;
            else if(lps[i] > 0) l1 ++;
            else l2 ++;
            ans += abs(lps[i]);
        }
        if(n == 1)
        {
            printf("%lld\n", lps[1]);
            continue;
        }
        if(flag == 1||(l1<n&&l1>0))
        {
            printf("%lld\n", ans);
        }
        if(l1 == n)
        {
            sort(lps+1, lps+1+n);
            printf("%lld\n", ans -= lps[1] * 2);
        }
        else if(l2 == n)
        {
            sort(lps+1, lps+1+n, cmp);
            printf("%lld\n", ans += lps[1] * 2);
        }
    }
    return 0;
}

/*

*/