#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <vector>
#define pb push_back

using namespace std;

vector<int>rise;

int main(){
    int n, a; cin >> n;
    for(int i=0; i<n; i++){
        cin >> a;
        rise.pb(a);
    }
    int max=0, count=0;
    for(int i=1; i<rise.size(); i++){
        if(rise[i]>rise[i-1]){
            count+=rise[i]-rise[i-1];
            if(count>max) max=count;
        }
        else count=0;
    }
    cout << max << endl;



    return 0;
}