经典dp

K-Box_2023牛客暑期多校训练营2 (nowcoder.com)

#include<bits/stdc++.h>
#define int long long
using namespace std;
typedef pair<int, int> PII;
const int N = 1e6 + 110, mod = 1e9 + 7;
int a[N];
int st[N];
int f[N][2];
signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int n;
    cin >> n;
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) cin >> st[i];

    for (int i = 1; i <= n; i++) {
        f[i][0] = max(f[i - 1][1], f[i - 1][0]);
        if (st[i]) {
            f[i + 1][1] = max(f[i][0], f[i][1]) + a[i + 1];
            f[i][1] = max(f[i - 1][0] + a[i], f[i - 1][1] + a[i]);
            f[i][0] = max(f[i - 1][0] + a[i - 1], f[i][0]);
        }
    }
    cout << max(f[n][1], f[n][0]) << "\n";
    return 0;
}