Submission #927890

#	Time	Username	Problem	Language	Result	Execution time	Memory
927890		sleepntsheep	Feast (NOI19_feast)	C++17	18 / 100	356 ms	22356 KiB

feast

#include <cstdio>
#include <cmath>
#include <climits>
#include <functional>
#include <numeric>
#include <cstring>
#include <cassert>
#include <string>
#include <deque>
#include <vector>
#include <map>
#include <queue>
#include <algorithm>
#include <iostream>
#include <utility>
using namespace std;
using ll=long long;

#define N 300005
#define ALL(x) x.begin(), x.end()

int n, k, a[N];
long long p[N];
pair<long double, int> dp[N][2];
const long double EPS = 1e-3;

int check(long double lambda)
{
    dp[0][1] = make_pair(-1e18, 0);
    for (int i = 1; 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] - lambda, 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]).second >= k;
}

int main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> k;
    for (int i = 1; i <= n; ++i) cin >> a[i];

    ll l = 0, r = 1e18;
    while (l <= r)
    {
        ll y = (l+r)/2;
        if (check(y)) l = y + 1;
        else r = y - 1;
    }

    check(l-1);
    cout << (long long)round(k * (l-1) + max(dp[n][0], dp[n][1]).first);

    return 0;
}

• Subtask 1: 0 / 4
• Subtask 2: 0 / 8
• Subtask 3: 18 / 18
• Subtask 4: 0 / 10
• Subtask 5: 0 / 11
• Subtask 6: 0 / 20
• Subtask 7: 0 / 29