Submission #1210090

#	Time	Username	Problem	Language	Result	Execution time	Memory
1210090		blazer	Feast (NOI19_feast)	C++20	100 / 100	116 ms	7460 KiB

feast

#include <bits/stdc++.h>

using namespace std;
#define int long long

int a[300005];
pair <int, int> dp[300005];

void calc(int n, int pen) {
    pair <int, int> mx = {0, 0};
    for (int i = 1; i <= n; i++) {
        dp[i] = max(dp[i - 1], {mx.first + a[i] - pen, mx.second - 1});
        mx = max(mx, {dp[i].first - a[i], dp[i].second});
    }
}

signed main() {
    int n, k;
    cin >> n >> k;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        a[i] += a[i - 1];
    }
    int l = 0, r = 1e15;
    while (l < r) {
        int mid = (l + r) / 2;
        calc(n, mid);
        if (-dp[n].second <= k) {
            r = mid;
        } else {
            l = mid + 1;
        }
    }
    calc(n, l);
    cout << dp[n].first + l * k;
}

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 18 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 29 / 29