#[allow(unused_macros)]
macro_rules! input {
    ( source = $ s : expr , $ ( $ r : tt ) * ) => { let mut iter = $ s . split_whitespace ( ) ; let mut next = || { iter . next ( ) . unwrap ( ) } ; input_inner ! { next , $ ( $ r ) * } };
    ( $ ( $ r : tt ) * ) => { let stdin = std :: io :: stdin ( ) ; let mut bytes = std :: io :: Read :: bytes ( std :: io :: BufReader :: new ( stdin . lock ( ) ) ) ; let mut next = move || -> String { bytes . by_ref ( ) . map ( | r | r . unwrap ( ) as char ) . skip_while ( | c | c . is_whitespace ( ) ) . take_while ( | c |! c . is_whitespace ( ) ) . collect ( ) } ; input_inner ! { next , $ ( $ r ) * } };
}
#[allow(unused_macros)]
macro_rules! input_inner {
    ( $ next : expr ) => { };
    ( $ next : expr , ) => { };
    ( $ next : expr , $ var : ident : $ t : tt $ ( $ r : tt ) * ) => { let $ var = read_value ! ( $ next , $ t ) ; input_inner ! { $ next $ ( $ r ) * } };
}
#[allow(unused_macros)]
macro_rules! read_value {
    ( $ next : expr , ( $ ( $ t : tt ) ,* ) ) => { ( $ ( read_value ! ( $ next , $ t ) ) ,* ) };
    ( $ next : expr , [ $ t : tt ; $ len : expr ] ) => { ( 0 ..$ len ) . map ( | _ | read_value ! ( $ next , $ t ) ) . collect ::< Vec < _ >> ( ) };
    ( $ next : expr , chars ) => { read_value ! ( $ next , String ) . chars ( ) . collect ::< Vec < char >> ( ) };
    ( $ next : expr , usize1 ) => { read_value ! ( $ next , usize ) - 1 };
    ( $ next : expr , $ t : ty ) => { $ next ( ) . parse ::<$ t > ( ) . expect ( "Parse error" ) };
}

#[allow(unused_macros)]
macro_rules! chmax {
    ( $ x : expr , $ y : expr ) => { if $ x < $ y { $ x = $ y ; true } else { false } };
}

fn main() {
    input! {
        n: usize,
        h: [usize; n],
        a: [u64; n]
    }

    let mut sq = SqDecomposition::new(n+1);
    for i in 0..n {
        sq.all[h[i]] = std::cmp::max(sq.all[h[i]], sq.max(h[i]) + a[i]);
        chmax!(sq.sq[h[i] / sq.d], sq.all[h[i]]);
    }
    println!("{}", sq.max(n+1));
}

#[derive(Debug)]
#[allow(dead_code)]
struct SqDecomposition {
    all: Vec<u64>,
    sq: Vec<u64>,
    d: usize,
}
#[allow(dead_code)]
impl SqDecomposition {
    fn new(n: usize) -> SqDecomposition {
        let d = (n as f64).sqrt().ceil() as usize;
        SqDecomposition {
            all: vec![0; n],
            sq: vec![0; d],
            d: d,
        }
    }
    fn max(&self, n: usize) -> u64 {
        let mut ret = 0;
        for i in 0..n / self.d {
            chmax!(ret, self.sq[i]);
        }
        for i in 0..n % self.d {
            chmax!(ret, self.all[n - n % self.d + i]);
        }
        ret
    }

    #[doc = " [0,n)"]
    fn sum(&self, n: usize) -> u64 {
        let mut ret = 0;
        for i in 0..n / self.d {
            ret += self.sq[i];
        }
        for i in 0..n % self.d {
            ret += self.all[n - n % self.d + i];
        }
        ret
    }
    fn lower_bound_of_sum(&self, mut sum: u64) -> usize {
        let mut i = 0;
        while sum > self.sq[i] {
            sum -= self.sq[i];
            i += 1;
        }
        for j in self.d * i..self.d * (i + 1) {
            if self.all[j] >= sum {
                return j;
            }
            sum -= self.all[j];
        }
        panic!();
    }
}

Measured memory_bytes: 10492