Submission #1211123

#	Time	Username	Problem	Language	Result	Execution time	Memory
1211123		balls	Feast (NOI19_feast)	C++20	100 / 100	166 ms	16844 KiB

feast

#include<bits/stdc++.h>
using namespace std;
#define int long long

const int MaxN = 3e5 + 7;
int a[MaxN], n, k;
pair<int, int> dp[MaxN][3];

pair<int, int> calc(int x) {
    dp[1][0] = {0, 0};
    dp[1][1] = {a[1] - x, 1};
    for (int i = 2; i <= n; i++) {
        dp[i][0] = max(dp[i - 1][0], dp[i - 1][1]);
        dp[i][1] = max(make_pair(dp[i - 1][0].first + a[i] - x, dp[i - 1][0].second + 1), make_pair(dp[i - 1][1].first + a[i], dp[i - 1][1].second));
    }
    return max(dp[n][0], dp[n][1]);
}

signed main() {
    cin >> n >> k;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
    }

    int l = 0, r = 1e18;
    while (l < r) {
        int mid = (l + r + 1) / 2;
        if (calc(mid).second >= k) {
            l = mid;
        } else {
            r = mid - 1;
        }
    }
    cout << calc(l).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