#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

typedef int _loop_int;
#define REP(i,n) for(_loop_int i=0;i<(_loop_int)(n);++i)
#define FOR(i,a,b) for(_loop_int i=(_loop_int)(a);i<(_loop_int)(b);++i)
#define FORR(i,a,b) for(_loop_int i=(_loop_int)(b)-1;i>=(_loop_int)(a);--i)

#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define DEBUG_VEC(v) cout<<#v<<":";REP(i,v.size())cout<<" "<<v[i];cout<<endl
#define ALL(a) (a).begin(),(a).end()

#define CHMIN(a,b) a=min((a),(b))
#define CHMAX(a,b) a=max((a),(b))

// mod
const ll MOD = 1000000007ll;
#define FIX(a) ((a)%MOD+MOD)%MOD

// floating
typedef double Real;
const Real EPS = 1e-11;
#define EQ0(x) (abs(x)<EPS)
#define EQ(a,b) (abs(a-b)<EPS)
typedef complex<Real> P;

int n;
int a[125252];

// ライブラリを整備しなさ～い！
const int N = 1<<17;
pll dat[2*N];
void qset(int x, pll v){
  x += N-1;
  CHMAX(dat[x], v);
  while(x){
    x=(x-1)/2;
    dat[x] = max(dat[2*x+1], dat[2*x+2]);
  }
}
pll qmax(int l, int r, int a, int b, int k){
  if(r<=a || b<=l)return pll(-1ll<<60,-1ll<<60);
  if(l<=a && b<=r)return dat[k];
  int m = (a+b)/2;
  return max(qmax(l,r,a,m,2*k+1), qmax(l,r,m,b,2*k+2));
}

int main(){
  scanf("%d",&n);
  REP(i,n)scanf("%d",a+i);
  fill(dat,dat+2*N,pll(0,0));
  pll ans = pll(0,0);
  REP(i,n){
    int v = a[i];
    pll s = pll(0,0);
    if(v==0){
      s = pll(1,0);
    }else{
      pll q = qmax(0,v,0,N,0);
      s = q;
      s.first++;
      s.second+=v;
    }
    CHMAX(ans, s);
    qset(v, s);
  }
  printf("%lld\n",ans.second);
  return 0;
}

