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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#372613#5111. Take On MemeshepherdWA 1ms3848kbC++205.7kb2024-03-31 16:41:392024-03-31 16:41:41

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你现在查看的是最新测评结果

  • [2024-03-31 16:41:41]
  • 评测
  • 测评结果:WA
  • 用时:1ms
  • 内存:3848kb
  • [2024-03-31 16:41:39]
  • 提交

answer

#include <bits/stdc++.h>

#pragma GCC optimize("O3,unroll-loops")

#ifdef LLOCAL
#include "debug.h"
#else
#define var(...)
#define debugArr(...)
#endif

using namespace std;

#define len(a) static_cast<int>((a).size())
#define present(c, x) (c.find(x) != c.end())
#define printDecimal(d) std::cout << std::setprecision(d) << std::fixed

using ll = long long;
using ull = unsigned long long;
using ld = long double;
constexpr const int iinf = 1e9 + 7;
constexpr const ll inf = 1e18;
constexpr const ll mod = 1'000'000'007;

template <typename Fun>
class y_combinator_result {
  Fun fun_;

 public:
  template <typename T>
  explicit y_combinator_result(T&& fun) : fun_(std::forward<T>(fun)) {}

  template <typename... Args>
  decltype(auto) operator()(Args&&... args) {
    return fun_(std::ref(*this), std::forward<Args>(args)...);
  }
};
template <typename Fun>
decltype(auto) y_combinator(Fun&& fun) {
  return y_combinator_result<std::decay_t<Fun>>(std::forward<Fun>(fun));
}

template <class T>
int sgn(T x) {
  return (x > 0) - (x < 0);
}
template <class T>
struct Point {
  typedef Point P;
  T x, y;
  explicit Point(T x = 0, T y = 0) : x(x), y(y) {}
  bool operator<(P p) const { return tie(x, y) < tie(p.x, p.y); }
  bool operator==(P p) const { return tie(x, y) == tie(p.x, p.y); }
  P operator+(P p) const { return P(x + p.x, y + p.y); }
  P operator-(P p) const { return P(x - p.x, y - p.y); }
  P operator*(T d) const { return P(x * d, y * d); }
  P operator/(T d) const { return P(x / d, y / d); }
  T dot(P p) const { return x * p.x + y * p.y; }
  T cross(P p) const { return x * p.y - y * p.x; }
  T cross(P a, P b) const { return (a - *this).cross(b - *this); }
  T dist2() const { return x * x + y * y; }
  double dist() const { return sqrt((double)dist2()); }
  // angle to x-axis in interval [-pi, pi]
  double angle() const { return atan2(y, x); }
  P unit() const { return *this / dist(); }  // makes dist()=1
  P perp() const { return P(-y, x); }        // rotates +90 degrees
  P normal() const { return perp().unit(); }
  // returns point rotated 'a' radians ccw around the origin
  P rotate(double a) const {
    return P(x * cos(a) - y * sin(a), x * sin(a) + y * cos(a));
  }
  friend ostream& operator<<(ostream& os, P p) {
    return os << "(" << p.x << "," << p.y << ")";
  }
};

using P = Point<ll>;
vector<P> convexHull(vector<P> pts) {
  if (len(pts) <= 1) return pts;
  sort(begin(pts), end(pts));
  vector<P> h(len(pts) + 1);
  int s = 0, t = 0;
  for (int it = 2; it--; s = --t, reverse(begin(pts), end(pts)))
    for (P p : pts) {
      while (t >= s + 2 && h[t - 2].cross(h[t - 1], p) <= 0) t--;
      h[t++] = p;
    }
  return {h.begin(), h.begin() + t - (t == 2 && h[0] == h[1])};
}

void rotate_polygon(vector<P>& poly) {
  size_t pos = 0;
  for (size_t i = 1; i < poly.size(); i++) {
    if (poly[i].y < poly[pos].y ||
        (poly[i].y == poly[pos].y && poly[i].x < poly[pos].x))
      pos = i;
  }
  rotate(begin(poly), begin(poly) + pos, end(poly));
}

vector<P> minkowski(vector<P> poly1, vector<P> poly2) {
  rotate_polygon(poly1);
  rotate_polygon(poly2);
  size_t n = poly1.size(), m = poly2.size();
  poly1.push_back(poly1[0]);
  poly1.push_back(poly1[1]);
  poly2.push_back(poly2[0]);
  poly2.push_back(poly2[1]);
  vector<P> ret;
  size_t i = 0, j = 0;
  while (i < n || j < m) {
    ret.push_back(poly1[i] + poly2[j]);
    auto c = (poly1[i + 1] - poly1[i]).cross(poly2[j + 1] - poly2[j]);
    i += c >= 0 && i < n;
    j += c <= 0 && j < m;
  }
  return ret;
}

int main() {
  std::ios_base::sync_with_stdio(false);
  cin.tie(0);
  int n;
  cin >> n;
  vector<vector<P>> candidates(n);
  vector<bool> is_leaf(n, false);
  vector<vector<int>> graph(n);
  for (int i = 0; i < n; i++) {
    int k;
    cin >> k;
    if (k == 0) {
      is_leaf[i] = true;
      int x, y;
      cin >> x >> y;
      candidates[i].emplace_back(x, y);
    } else {
      for (int j = 0; j < k; j++) {
        int x;
        cin >> x;
        graph[i].push_back(--x);
      }
    }
  }
  auto neg = [&](const vector<P>& pts) {
    vector<P> ret;
    for (const auto& p : pts) {
      ret.emplace_back(-p.x, -p.y);
    }
    return ret;
  };
  auto solve = y_combinator([&](auto self, int curr) -> void {
    if (is_leaf[curr]) return;
    vector<P> sum_neg;
    vector<vector<P>> left, right;
    for (const auto& neighbor : graph[curr]) {
      self(neighbor);
      if (!sum_neg.empty()) {
        left.push_back(minkowski(candidates[neighbor], sum_neg));
      } else {
        left.emplace_back();
      }
      if (sum_neg.empty()) {
        sum_neg = candidates[neighbor];
      } else {
        sum_neg = minkowski(sum_neg, neg(candidates[neighbor]));
      }
    }
    sum_neg.clear();
    for (int i = len(graph[curr]) - 1; i >= 0; i--) {
      auto neighbor = graph[curr][i];
      if (!sum_neg.empty()) {
        right.push_back(minkowski(candidates[neighbor], sum_neg));
      } else {
        right.emplace_back();
      }
      if (sum_neg.empty()) {
        sum_neg = candidates[neighbor];
      } else {
        sum_neg = minkowski(sum_neg, neg(candidates[neighbor]));
      }
    }
    for (int i = 0; i < len(graph[curr]); i++) {
      left[i].insert(left[i].end(), right[i].begin(), right[i].end());
      left[i] = convexHull(left[i]);
      candidates[curr].insert(candidates[curr].end(), left[i].begin(),
                              left[i].end());
    }
    candidates[curr] = convexHull(candidates[curr]);
  });
  solve(0);
  ll ret = 0;
  for (const auto& elem : candidates[0]) {
    ret = max(ret, elem.dist2());
  }
  cout << ret << '\n';
}

详细

Test #1:

score: 0
Wrong Answer
time: 1ms
memory: 3848kb

input:

5
4 2 3 4 5
0 2 -2
0 1 3
0 4 -6
0 -18 5

output:

637

result:

wrong answer 1st lines differ - expected: '725', found: '637'