Submission #258682

#	Time	Username	Problem	Language	Result	Execution time	Memory
258682		fedoseevtimofey	Space Pirate (JOI14_space_pirate)	C++14	47 / 100	1305 ms	213112 KiB

space_pirate

#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <random>
#include <iomanip>
#include <functional>
#include <cassert>

using namespace std;

typedef long long ll;

const int N = 3007;
const int K = 60;

int go[K][N];
int slow_go[N][4 * N];
ll min_dist[N][N];
int cycle_len[N];
bool used[N];

int big_step(ll x) {
  return 63 - __builtin_clzll(x);
}

int main() {
  ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
  freopen("input.txt", "r", stdin);
#endif
  int n; ll k;
  cin >> n >> k;
  vector <int> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    --a[i];
  }
  for (int i = 0; i < n; ++i) {
    go[0][i] = a[i];
  }
  for (int i = 1; i < K; ++i) {
    for (int j = 0; j < n; ++j) {
      go[i][j] = go[i - 1][go[i - 1][j]];
    }
  }
  for (int i = 0; i < n; ++i) {
    int u = go[K - 1][i];
    if (used[u]) continue;
    int len = 1;
    int v = a[u];
    while (v != u) {
      v = a[v];
      ++len;
    }
    used[u] = 1;
    cycle_len[u] = len;
    v = a[u];
    while (v != u) {
      used[v] = 1;
      cycle_len[v] = len;
      v = a[v];
    }
  }
  auto get = [&] (int u, ll x) {
    if (x <= 4 * n) return slow_go[u][x];
    int p2 = big_step(x);
    u = go[p2][u];
    x -= (1LL << p2);
    x %= cycle_len[u];
    u = slow_go[u][x];
    return u;
  };

  for (int i = 0; i < n; ++i) {
    slow_go[i][0] = i;
    slow_go[i][1] = a[i];
    for (int j = 2; j <= 4 * n; ++j) {
      slow_go[i][j] = a[slow_go[i][j - 1]];
    }
  }
  int gogo = get(0, k);
  const ll Inf = 2e18;
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < n; ++j) {
      min_dist[i][j] = Inf;
    }
  }
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j <= n; ++j) {
      min_dist[i][slow_go[i][j]] = min(min_dist[i][slow_go[i][j]], (ll)j);
    }
  }   
  vector <int> cnt(n);
  for (int x = 0; x < n; ++x) {
    for (int y = 0; y < n; ++y) {
      ll cur_k = 0;
      int u = 0;
      if (min_dist[u][x] > (k - cur_k)) {
        ++cnt[gogo];
        continue;
      }
      cur_k = min_dist[u][x];
      u = x;
      if (cur_k < k && u == x) {
        u = y;
        ++cur_k;
      }
      if (min_dist[u][x] > (k - cur_k)) {
        ++cnt[get(u, k - cur_k)];
        continue;
      }
      ll cycle_len = min_dist[u][x];
      cur_k += min_dist[u][x];
      u = x;
      if (cur_k < k && u == x) {
        ++cur_k;
        ++cycle_len;
        u = y;
      }
      if (cur_k < k) {
        ll need = (k - cur_k) % cycle_len;
        u = get(u, need);
      }
      ++cnt[u];
    }
  }
  for (int i = 0; i < n; ++i) {
    cout << cnt[i] << '\n';
  }
}

• Subtask 1: 10 / 10
• Subtask 2: 37 / 37
• Subtask 3: 0 / 33
• Subtask 4: 0 / 20