#include <cstdio>
#include <algorithm>

using namespace std;

int n, data [ 10005 ], rj = 0;

int main ( void ) {

    scanf ( "%d", &n );

    for ( int i = 0; i < n; ++i )
        scanf ( "%d", &data [ i ] );

    bool idem = true; int raz = 0;
    for ( int i = 1; i <= n; ++i ) {
        if ( data [ i ] > data [ i - 1 ] ) {
            idem = true;
            raz += data [ i ] - data [ i - 1 ];
        }
        else {
            idem = false;
            rj = max ( rj, raz );
            raz = 0;
        }
    }

    printf ( "%d\n", rj );

    return 0;
}