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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 Meme | shepherd | WA | 1ms | 3848kb | C++20 | 5.7kb | 2024-03-31 16:41:39 | 2024-03-31 16:41:41 |
Judging History
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'