#include <iostream>
using namespace std;
int main()
{
cout.setf(ios::fixed);
cout.precision(0);
int n,c;
cin>>n;
long double suma=0;
long double makskasa=0;
while (n--)
{
cin >>c;
suma+=c;
if (makskasa<suma)
{
makskasa=suma;
}
if (0>suma)
{
suma=0;
}
}
cout<<makskasa << endl ;
return 0;
}
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