【第14题】CF987C Three displays

const LL INF = 0x7f7f7f7f7f7f7f;

#include <vector>
#include <iostream>

using namespace std;
#define endl '\n';
typedef long long LL;

const LL INF = 0x7f7f7f7f7f7f7f;

void best_coder() {
    LL ans = INF;
    int n;
    scanf("%d", &n);
    vector<vector<LL>> dp(n, vector<LL>(3, INF));
    vector<LL> s(n);
    vector<LL> c(n);
    for (int i = 0; i < n; ++i) {
        scanf("%d", &s[i]);
    }
    for (int i = 0; i < n; ++i) {
        scanf("%d", &c[i]);
    }
    for (int i = 0; i < n; ++i) {
        dp[i][0] = c[i];
        for (int k = 1; k < 3; ++k) {
            for (int j = 0; j < i; ++j) {
                if (s[j] < s[i]) {
                    dp[i][k] = min(dp[i][k], dp[j][k - 1] + c[i]);
                }
            }
        }
        ans = min(ans, dp[i][2]);
    }
    if (ans == INF) {
        printf("%d\n", -1);
    } else {
        printf("%lld\n", ans);
    }
}

void happy_coder() {
}

int main() {
    // 提升cin、cout效率
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    // 小码匠
    best_coder();

    // 最优解
    // happy_coder();

    // 返回
    return 0;
}