#include<iostream>
using namespace std;
long long jia,jian,xz,n,a[200005],ans;
int main()
{
    cin>>n;
    for(int i=1;i<=n;i++)cin>>a[i];
    for(int i=1;i<=n;i++)
    {

        xz
        if(a[i]<0)
        {
            cout<<"iii"<<endl;
            int u=a[i]*-1;
            ans+=u;
        }
        if(a[i]>0)
        {
            cout<<"ooo"<<endl;
            xz-=a[i];
            ans+=a[i];
        }
    }
    cout<<jia+jian;
    return 0;
}