#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    long long maxx=-1145141919810,minn=1145141919810;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        long long a;
        cin>>a;
        maxx=max(maxx,a-minn);
        minn=min(minn,a);
    }
    cout<<maxx;
    return 0;
}