#include <iostream>
using namespace std;

const int N = 100010;
int a[N];

int main() {
    int n;
    cin >> n;
    for(int i = 0; i < n; i ++){
        cin >> a[i];
    }
    int minPrice = 1e9, maxProfit = -1e9;
    for(int i = 0; i < n; i ++){
        minPrice = min(a[i], minPrice);
        maxProfit = max(maxProfit, a[i] - minPrice);
    }
    cout << maxProfit << endl;
    return 0;
}