#include <iostream>
#include <cstdlib>
#include <cmath>
using namespace std;

int main()
{
    int n, put[1001], max=0, sum=0;
    scanf("%d", &n);
    for (int i=0;i<n;++i)
        scanf("%d", &put[i]);
    for (int i=1;i<n;++i)
    {
        if (put[i]>put[i-1])
           sum+=(put[i]-put[i-1]);
        else
        {
            if (sum>max)
               max=sum;
            sum=0;
        }
    }
    if (sum>max)
       max=sum;
    printf("%d\n", max);
    return 0;
}