제출 #1320988

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1320988		tolga	Feast (NOI19_feast)	C++20	4 / 100	69 ms	9684 KiB

feast

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define endl '\n'

int n, k;
vector<ll> a;

pair<ll, int> check(ll cost) {
  vector<array<ll, 2>> dp(n + 1);
  vector<int> cnt0(n + 1), cnt1(n + 1);

  dp[1][1] = a[0] - cost;
  cnt1[1] = 1;

  for (int i = 1; i <= n; i++) {
    if (dp[i - 1][0] > dp[i - 1][1]) {
      dp[i][0] = dp[i - 1][0];
      cnt0[i] = cnt0[i - 1];
    } else {
      dp[i][0] = dp[i - 1][1];
      cnt0[i] = cnt1[i - 1];
    }
    if (dp[i - 1][0] + cost > dp[i - 1][1]) {
      dp[i][1] = dp[i - 1][0] + a[i - 1] + cost;
      cnt1[i] = cnt0[i - 1] + 1;
    } else {
      dp[i][1] = dp[i - 1][1] + a[i - 1];
      cnt1[i] = cnt1[i - 1] + 1;
    }
  }

  if (dp[n][0] == dp[n][1])
    return {dp[n][0], max(cnt0[n], cnt1[n])};

  if (dp[n][0] > dp[n][1])
    return {dp[n][0], cnt0[n]};
  else
    return {dp[n][1], cnt1[n]};
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr), cout.tie(nullptr);

  cin >> n >> k;
  a.resize(n);
  for (int i = 0; i < n; i++)
    cin >> a[i];

  ll left = 0, right = 5 + 3e5;
  while (left <= right) {
    ll mid = (left + right) / 2;
    if (check(mid).second >= k)
      right = mid - 1;
    else
      left = mid + 1;
  }
  cout << check(right).first << endl;
}

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