Submission #24101

#	Time	Username	Problem	Language	Result	Execution time	Memory
24101		jiaqiyang	City (JOI17_city)	C++14	100 / 100	549 ms	57928 KiB

Encoder

#include "Encoder.h"
#include <vector>
#include <algorithm>

static const int N = 250000 + 10;

typedef long long i64;

static std::vector<int> adj[N], r;

static void init() {
  int i = 1;
  for (; i < N; i += std::max<int>(1, .05 * i)) r.push_back(i);
  for (int j = 20; j--; i += std::max<int>(1, .05 * i)) r.push_back(i);
}

static int left[N], right[N], tot;

static void dfs(int a, int fa = -1) {
  left[a] = tot++;
  for (int i = 0; i < adj[a].size(); ++i) if (adj[a][i] != fa) dfs(adj[a][i], a);
  right[a] = tot = left[a] + *std::lower_bound(r.begin(), r.end(), tot - left[a]);
}

void Encode(int n, int a[], int b[]) {
  init();
  for (int i = 0; i < n - 1; ++i) adj[a[i]].push_back(b[i]), adj[b[i]].push_back(a[i]);
  dfs(0);
  for (int i = 0; i < n; ++i) {
    int x = left[i], y = std::lower_bound(r.begin(), r.end(), right[i] - left[i]) - r.begin();
    Code(i, y << 20 | x);
  }
}

Device

#include "Device.h"
#include <vector>
#include <algorithm>

static const int N = 250000 + 10;

typedef long long i64;

static std::vector<int> r;

void InitDevice() {
  int i = 1;
  for (; i < N; i += std::max<int>(1, .05 * i)) r.push_back(i);
  for (int j = 20; j--; i += std::max<int>(1, .05 * i)) r.push_back(i);
}

static std::pair<int, int> solve(i64 x) {
  int l = x & 0xfffff, y = x >> 20;
  return std::make_pair(l, l + r[y]);
}

int Answer(i64 s, i64 t) {
  std::pair<int, int> x = solve(s), y = solve(t);
  if (y.first <= x.first && x.second <= y.second) return 0;
  if (x.first <= y.first && y.second <= x.second) return 1;
  return 2;
}

Compilation message (stderr)

Encoder.cpp: In function 'void dfs(int, int)':
Encoder.cpp:21:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < adj[a].size(); ++i) if (adj[a][i] != fa) dfs(adj[a][i], a);
                   ~~^~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 92 / 92