#include <iostream>
using namespace std;
const int N = 1e5 + 10;
typedef long long ll;
ll v[N];
int main(){
    int n;  cin >> n;
    ll minv = 1e9 + 10;
    ll res = 0;
    for(int i = 0; i < n; i ++ ){
        cin >> v[i];
        minv = min(minv, v[i]);
        res = max(v[i] - minv, res);
    }
    cout << res << endl;
    return 0;
}