Submission #224272

#	Time	Username	Problem	Language	Result	Execution time	Memory
224272		bortoz	Solar Storm (NOI20_solarstorm)	C++17	100 / 100	409 ms	130652 KiB

SolarStorm

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
#define fi first
#define se second

constexpr int MAXN = 1 << 20, LOGN = 21;

int J[LOGN][MAXN];
ll D[MAXN];
ll C[MAXN];
int lx[MAXN], rx[MAXN];

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

  int N, S;
  ll K;
  cin >> N >> S >> K;

  for (int i = 2; i <= N; i++) {
    cin >> D[i];
    D[i] += D[i - 1];
  }

  for (int i = 1; i <= N; i++) {
    cin >> C[i];
    C[i] += C[i - 1];
  }

  rx[0] = 1;
  for (int i = 1, l = 1, r = 1, x = 0; i <= N; i++) {
    while (r <= N && D[r] <= D[i] + K) r++;
    while (D[l] + K < D[i]) l++;
    while (rx[x] < l) x++;
    lx[i] = l;
    rx[i] = r;
    J[0][i] = x;
  }

  for (int k = 1; k < LOGN; k++) {
    for (int i = 1; i <= N; i++) {
      J[k][i] = J[k - 1][J[k - 1][i]];
    }
  }

  ll res = 0;
  int pos = 0;
  for (int i = 1; i <= N; i++) {
    int x = i;
    for (int k = 0; k < LOGN; k++) {
      if ((S - 1) & 1 << k) x = J[k][x];
    }
    ll T = C[rx[i] - 1] - C[lx[x] - 1];
    if (T > res) {
      res = T;
      pos = i;
    }
  }

  vector<int> sol;
  for (int i = 0; i < S && pos > 0; i++) {
    sol.push_back(pos);
    pos = J[0][pos];
  }
  reverse(sol.begin(), sol.end());

  cout << sol.size() << '\n';
  for (int i = 0; i < sol.size(); i++) {
    cout << sol[i] << " \n"[i + 1 == sol.size()];
  }

  return 0;
}

Compilation message (stderr)

SolarStorm.cpp: In function 'int main()':
SolarStorm.cpp:70:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < sol.size(); i++) {
                   ~~^~~~~~~~~~~~
SolarStorm.cpp:71:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     cout << sol[i] << " \n"[i + 1 == sol.size()];
                             ~~~~~~^~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 7 / 7
• Subtask 3: 11 / 11
• Subtask 4: 8 / 8
• Subtask 5: 18 / 18
• Subtask 6: 16 / 16
• Subtask 7: 30 / 30