#include <bits/stdc++.h>
using namespace std;
 
vector<int> H, W;
 
int main()
{
    int n;
    cin >> n;
    W.resize(n);
    for (int i = 0; i < n; ++i) {
        cin >> W[i];
    }
    H.resize(n);
    for (int i = 0; i < n; ++i) {
        cin >> H[i];
    }
    int a = 0;
    for (int i = 0; i < n; ++i) {
        int l = 0;
        for (int j = i - 1; j >= 0; --j) {
            if (W[j] < W[i] && H[j] > H[i] && W[j] > l) {
                l = W[j];
            }
        }
        int r = 0;
        for (int j = i + 1; j < n; ++j) {
            if (W[i] < W[j] && H[i] > H[j] && W[j] > r) {
                r = W[j];
            }
        }
        if (l > 0 && r > 0) {
            a = max(a, l + W[i] + r);
        }
    }
    cout << a << endl;
    return 0;
}

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

OAoyMjUgMjAwIDE1MCAzMDAgMjc1IDE3NSAyNTAgMjYwCjE0MCAxNTAgMTcwIDEwMCAxMTAgMTYwIDEzMCAxMjA=

8
225 200 150 300 275 175 250 260
140 150 170 100 110 160 130 120