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답안 #495602

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
495602 2021-12-19T12:58:03 Z 600Mihnea 3단 점프 (JOI19_jumps) C++17
32 / 100
 4000 ms 35484 KB 
#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];

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

  for (int r = n; r >= 1; r--) {
    for (auto &it : questionsAt[r]) {
      int l = it.l;
      int ind = it.ind;

      int best = 0;

      for (auto &offer : offers) {
        if (l <= offer.lft) {
          best = max(best, offer.value + getMaxA(offer.rgh, r));
        }
      }

      sol[ind] = best;
    }
  }

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



  return 0;
}

Subtask #1
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 9 ms 12052 KB Output is correct
2 Correct 6 ms 12060 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12060 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 7 ms 12108 KB Output is correct
7 Correct 7 ms 12044 KB Output is correct
8 Correct 6 ms 12068 KB Output is correct
9 Correct 6 ms 12064 KB Output is correct
10 Correct 6 ms 12108 KB Output is correct

Subtask #2
0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 9 ms 12052 KB Output is correct
2 Correct 6 ms 12060 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12060 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 7 ms 12108 KB Output is correct
7 Correct 7 ms 12044 KB Output is correct
8 Correct 6 ms 12068 KB Output is correct
9 Correct 6 ms 12064 KB Output is correct
10 Correct 6 ms 12108 KB Output is correct
11 Execution timed out 4075 ms 26380 KB Time limit exceeded
12 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 59 ms 35428 KB Output is correct
2 Correct 44 ms 33772 KB Output is correct
3 Correct 43 ms 32388 KB Output is correct
4 Correct 52 ms 35468 KB Output is correct
5 Correct 59 ms 35484 KB Output is correct
6 Correct 54 ms 34960 KB Output is correct
7 Correct 52 ms 34796 KB Output is correct
8 Correct 47 ms 34880 KB Output is correct
9 Correct 48 ms 35112 KB Output is correct

Subtask #4
0 / 54.0

# 결과 실행 시간 메모리 Grader output
1 Correct 9 ms 12052 KB Output is correct
2 Correct 6 ms 12060 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12060 KB Output is correct
5 Correct 7 ms 12068 KB Output is correct
6 Correct 7 ms 12108 KB Output is correct
7 Correct 7 ms 12044 KB Output is correct
8 Correct 6 ms 12068 KB Output is correct
9 Correct 6 ms 12064 KB Output is correct
10 Correct 6 ms 12108 KB Output is correct
11 Execution timed out 4075 ms 26380 KB Time limit exceeded
12 Halted 0 ms 0 KB -