#include <bits/stdc++.h>

using namespace std;

#define int long long
#define fir first
#define sec second
#define mkp make_pair 
#define pb push_back
#define lep( i, l, r ) for ( int i = ( l ); i <= ( r ); ++ i )
#define rep( i, r, l ) for ( int i = ( r ); i >= ( l ); -- i )

typedef long long ll;
typedef long double ld;
typedef pair < int, int > pii;

char _c; bool _f; template < class type > inline void read ( type &x ) {
	_f = 0, x = 0;
	while ( _c = getchar (), !isdigit ( _c ) ) if ( _c == '-' ) _f = 1;
	while ( isdigit ( _c ) ) x = x * 10 + _c - '0', _c = getchar (); if ( _f ) { x = -x; }
}

template < class type > inline void chkmin ( type &x, type y ) { x = ( x <= y ? x : y ); }
template < class type > inline void chkmax ( type &x, type y ) { x = ( x >= y ? x : y ); }

const int N = 1e6 + 5;

int n;
int t[N], a[N], f[N];

struct Node {
  int l, r, val, mid;
} b[N];

void Solve () {
  cin >> n;
  for ( int i = 1; i <= n; i ++ ) {
    cin >> t[i];
  }
  for ( int i = 1; i <= n; i ++ ) {
    cin >> a[i];
    a[i] *= t[i];
    b[i].l = max ( 1ll, i - t[i] + 1 ), b[i].r = min ( n, i + t[i] - 1 ), b[i].val = a[i];
    b[i].mid = i;
  }
  sort ( b + 1, b + 1 + n, [] ( Node x, Node y ) { return x.r == y.r ? x.l < y.l : x.r < y.r; } );
  int ans = 0;
  for ( int i = 1; i <= n; i ++ ) {
    for ( int j = 0; j < i; j ++ ) {
      if ( b[j].r < b[i].mid && b[i].l > b[j].mid ) {
        f[i] = max ( f[i], f[j] + b[i].val );
      }
    }
    ans = max ( ans, f[i] );
  }
  cout << ans;
}

signed main () {
#ifdef judge
  freopen ( "Code.in", "r", stdin );
  freopen ( "Code.out", "w", stdout );
  freopen ( "Code.err", "w", stderr );
#endif
  Solve ();
	return 0;
}