Submission #573922

# Submission time Handle Problem Language Result Execution time Memory
573922 2022-06-07T12:14:00 Z lumibons Flight to the Ford (BOI22_communication) C++17
100 / 100
3471 ms 2080 KB
#include <vector>
#include "communication.h"

typedef long long ll;

using namespace std;

struct interval {
  ll l, r;
  interval(ll l, ll r) : l(l), r(r) {}
  bool contains(ll x) {
    return l <= x && x < r;
  }
  ll length() {
    return r - l;
  }
  interval shrink(ll o, ll s) {
    return interval(min(r, l + o), min(r, l + o + s));
  }
};

vector<interval> splitIntervals(vector<interval> c, ll o, ll s) {
  vector<interval> r;
  for (interval &it : c) {
    if (s > 0 && it.length() - o > 0)
      r.push_back(it.shrink(o, s));
    s -= max(0LL, min(s, it.length() - o));
    o -= min(o, it.length());
  }
  return r;
}

bool contains(vector<interval> c, ll x) {
  for (interval &it : c)
    if (it.contains(x))
      return true;
  return false;
}

struct state {
  ll s[2] = {0, 0};
  vector<vector<interval>> c;
  state(ll N): c(2) {
    s[1] = N;
    c[1].emplace_back(1, N + 1);
  }
  state(vector<vector<vector<interval>>> &cs): c(2) {
    for (int g = 0; g < 2; g++)
      for (vector<interval> &c : cs[g])
        add(g, c);
  }
  void add(int g, interval it) {
    s[g] += it.length();
    c[g].push_back(it);
  }
  void add(int g, vector<interval> &c) {
    for (interval &it : c)
      add(g, it);
  }
  vector<vector<vector<interval>>> split() {
    vector<vector<vector<interval>>> r(2);
    for (int g = 0; g < 2; g++) {
      int s1 = (s[g] + g) / 2, s2 = s[g] - s1;
      r[g].push_back(splitIntervals(c[g], 0, s1));
      r[g].push_back(splitIntervals(c[g], s1, s2));
    }
    return r;
  }
  ll size() {
    return s[0] + s[1];
  }
  vector<ll> remaining() {
    vector<ll> r;
    for (int g = 0; g < 2; g++)
      for (interval &it : c[g])
        for (ll v = it.l; v < it.r; v++)
          r.push_back(v);
    return r;
  }
};

std::pair<int, int> solve(int N, int X = -1) {
  state s(N);
  while (s.size() > 3) {
    vector<vector<vector<interval>>> c = s.split();
    int b = X != -1 ? send(contains(c[0][0], X) || contains(c[1][0], X)) : receive();
    c[0].erase(c[0].begin() + b);
    swap(c[0][0], c[1][b]);
    s = state(c);
  }
  vector<ll> r = s.remaining();
  if ((int) r.size() == 3) {
    int b1 = 1, b2;
    for (int i = 0; i < 2 && b1; i++)
      b1 = X != -1 ? send(r[0] == X || r[1] == X) : receive();
    if (!b1)
      b2 = X != -1 ? send(r[0] == X) : receive();
    r.erase(r.begin() + (b1 ? 2 : (b2 ? 1 : 0)));
  }
  return {r[0], r.back()};
}

void encode(int N, int X) {
  solve(N, X);
}

std::pair<int, int> decode(int N) {
  return solve(N);
}
# Verdict Execution time Memory Grader output
1 Correct 8 ms 1636 KB Output is correct
2 Correct 12 ms 1712 KB Output is correct
3 Correct 9 ms 1760 KB Output is correct
4 Correct 7 ms 1764 KB Output is correct
5 Correct 11 ms 1676 KB Output is correct
6 Correct 18 ms 1800 KB Output is correct
7 Correct 40 ms 1720 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 685 ms 1844 KB Output is correct
2 Correct 300 ms 1780 KB Output is correct
3 Correct 335 ms 1740 KB Output is correct
4 Correct 920 ms 1800 KB Output is correct
5 Correct 674 ms 1968 KB Output is correct
6 Correct 597 ms 1760 KB Output is correct
7 Correct 2087 ms 1872 KB Output is correct
8 Correct 3422 ms 2080 KB Output is correct
9 Correct 3054 ms 1900 KB Output is correct
10 Correct 2988 ms 1860 KB Output is correct
11 Correct 2863 ms 2004 KB Output is correct
12 Correct 3143 ms 1928 KB Output is correct
13 Correct 3058 ms 1940 KB Output is correct
14 Correct 2895 ms 2012 KB Output is correct
15 Correct 1557 ms 1900 KB Output is correct
16 Correct 3471 ms 1880 KB Output is correct
17 Correct 793 ms 1832 KB Output is correct
18 Correct 792 ms 1940 KB Output is correct
19 Correct 879 ms 1876 KB Output is correct
20 Correct 926 ms 1792 KB Output is correct
21 Correct 816 ms 1968 KB Output is correct
22 Correct 800 ms 1876 KB Output is correct
23 Correct 1327 ms 1928 KB Output is correct
24 Correct 8 ms 1704 KB Output is correct
25 Correct 9 ms 1692 KB Output is correct
26 Correct 14 ms 1696 KB Output is correct
27 Correct 11 ms 1696 KB Output is correct
28 Correct 8 ms 1668 KB Output is correct
29 Correct 18 ms 1672 KB Output is correct
30 Correct 28 ms 1636 KB Output is correct