#include<bits/stdc++.h>
#define LL long long
#define GG long long
#define For(i, j, k) for(int i=j; i<=k; i++)
#define Dow(i, j, k) for(int i=j; i>=k; i--)
using namespace std;
inline GG read() {
GG x = 0, f = 1;
char ch = getchar();
while(ch<'0'||ch>'9') { if(ch=='-') f = -1; ch = getchar(); }
while(ch>='0'&&ch<='9') { x = x*10+ch-48; ch = getchar(); }
return x * f;
}
int n;
int f[1011], h[1011];
int main() {
int i = 1;
while(~scanf("%d", &n) && n) {
For(i, 1, n) h[i] = read();
For(i, 1, n) f[i] = h[i];
For(i, 2, n)
For(j, 1 ,i-1)
if(h[j]<h[i] && f[j]+h[i]>f[i])
f[i] = f[j]+h[i];
int k = 0;
For(i, 1, n) if(f[k] < f[i]) k = i;
printf("%d\n", f[k]);
}
return 0;
}