제출 #495608

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
495608		600Mihnea	3단 점프 (JOI19_jumps)	C++17	5 / 100	4043 ms	33792 KiB

jumps

#include <bits/stdc++.h>

using namespace std;

const int N = (int) 5e5 + 7;
const int K = 19;
const int INF = (int) 1e9 + 7;
int n;
int q;
int a[N];
int lg[N];
int maxA[K][N];
int nextBigger[N];

int getMaxA(int l, int r) {
  if (l > r) {
    return -INF;
  }
  assert(1 <= l && l <= r && r <= n);
  int k = lg[r - l + 1];
  return max(maxA[k][l], maxA[k][r - (1 << k) + 1]);
}

struct Offer {
  int value;
  int lft;
  int rgh;
};

struct Question {
  int l;
  int r;
  int ind;
};

bool operator < (Offer a, Offer b) {
  return a.lft > b.lft;
}

vector<Question> questionsAt[N];
int best[N];


signed main() {
  ios::sync_with_stdio(0); cin.tie(0);

  //freopen ("input", "r", stdin);


  cin >> n;
  for (int i = 2; i <= n; i++) {
    lg[i] = lg[i / 2] + 1;
  }
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    maxA[0][i] = a[i];
  }
  for (int k = 1; (1 << k) <= n; k++) {
    for (int i = 1; i + (1 << k) - 1 <= n; i++) {
      maxA[k][i] = max(maxA[k - 1][i], maxA[k - 1][i + (1 << (k - 1))]);
    }
  }

  { /// just some stack bro
    vector<int> stk;
    for (int i = n; i >= 1; i--) {
      while (!stk.empty() && a[i] >= a[stk.back()]) {
        stk.pop_back();
      }
      nextBigger[i] = (stk.empty() ? (n + 1) : stk.back());
      stk.push_back(i);
    }
  }

  vector<Offer> offers;

  for (int i = 1; i <= n; i++) {
    for (int j = i + 1; j <= min(n, nextBigger[i]); j = nextBigger[j]) {
      if (2 * j - i <= n) {
        offers.push_back({a[i] + a[j], i, 2 * j - i});
      }
    }
  }

  sort(offers.begin(), offers.end());


  cin >> q;
  vector<int> solPrint(q, -1);
  for (int i = 0; i < q; i++) {
    int l, r;
    cin >> l >> r;
    questionsAt[l].push_back({l, r, i});
  }

  for (int i = 1; i <= n; i++) {
    best[i] = -INF;
  }

  int last = -1;

  for (int l = n; l >= 1; l--) {
    while (last + 1 < (int) offers.size() && l <= offers[last + 1].lft) {
      last++;
    }
    for (int r = l; r <= n; r++) {
      for (int j = 0; j <= last; j++) {
        if (offers[j].rgh <= r) {
          best[r] = max(best[r], offers[j].value + a[r]);
        }
      }
    }
    for (auto &it : questionsAt[l]) {
      int r = it.r, ind = it.ind, maximum = 0;
      for (int j = l; j <= r; j++) {
        maximum = max(maximum, best[j]);
      }
      solPrint[ind] = maximum;
    }
  }

  for (auto &x : solPrint) {
    assert(x != -1);
    cout << x << "\n";
  }



  return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 27
• Subtask 4: 0 / 54