#include <bits/stdc++.h>
using namespace std;
#define ssuyu                                                                  \
    ios_base::sync_with_stdio(0);                                              \
    cin.tie(0)
#define pb push_back
#define F first
#define S second
#define pii pair<int, int>
#define int long long
#define PI acos(-1)
#define all(x) (x).begin(), (x).end()
const int N = 1e5 + 5;
int n, a[N] = {0}, dpmx1[N], dpmx2[N], dpmn1[N], dpmn2[N], ans = -1;

signed main() {

    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    dpmx1[0] = dpmn2[0] = a[0];
    for (int i = 1; i < n; i++) {
        dpmx1[i] = max(dpmx1[i - 1] + a[i], a[i]);
        dpmn2[i] = min(dpmn2[i - 1] + a[i], a[i]);
    }

    for (int i = 1; i < n; i++) {
        dpmx1[i] = max(dpmx1[i - 1] + a[i], a[i]);
        dpmn2[i] = min(dpmn2[i - 1] + a[i], a[i]);
    }
    reverse(a, a + n);
    dpmn1[0] = dpmx2[0] = a[0];
    for (int i = 1; i < n; i++) {
        dpmx2[i] = max(dpmx2[i - 1] + a[i], a[i]);
        dpmn1[i] = min(dpmn1[i - 1] + a[i], a[i]);
    }
    for (int i = 0; i < n; i++) {
        ans = max(ans, abs(dpmx1[i] - dpmn1[n - i - 2]));
        ans = max(ans, abs(dpmx2[i] - dpmn2[n - i - 2]));
    }

    cout << ans;
}