#include <iostream>
#define INF 2147000000
using namespace std;
int n, v[1005], i, maxx = - INF;
bool ok;
int main()
{
cin >> n;
for(i = 1; i <= n; i ++)
{
cin >> v[i];
if(v[i] < 0 && v[i] > maxx) maxx = v[i], ok = true;
}
if(ok) cout << maxx;
else cout << "Nu exista";
return 0;
}