Submission #683358

#	Time	Username	Problem	Language	Result	Execution time	Memory
683358		flappybird	Cultivation (JOI17_cultivation)	C++17	0 / 100	251 ms	262144 KiB

cultivation

#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx,avx2,fma")
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
#define MAX 310
#define MAXS 20
#define INF 1e9
#define bb ' '
#define ln '\n'
#define Ln '\n'
#define fmax(a, b) a = max(a, b)
#ifdef _MSC_VER
#  include <intrin.h>
#  define __builtin_popcount __popcnt
#endif
int X[MAX];
int Y[MAX];
int N, R, C;
int l[MAX];
int r[MAX];
int M;
int limu[MAX];
int limd[MAX];
int lims[MAX];
vector<int> st[MAX];
vector<int> en[MAX];
int mn;
int chk(int hor) {
	int i;
	vector<int> ys = { mn };
	for (i = 1; i <= N; i++) ys.push_back(Y[i]), ys.push_back(Y[i] + C + 1), ys.push_back(Y[i] + hor + 1);
	for (i = 1; i <= N; i++) ys.push_back(Y[i] + C), ys.push_back(Y[i] + hor);
	sort(ys.begin(), ys.end());
	ys.erase(unique(ys.begin(), ys.end()), ys.end());
	for (i = 1; i <= N; i++) {
		l[i] = lower_bound(ys.begin(), ys.end(), Y[i]) - ys.begin();
		r[i] = lower_bound(ys.begin(), ys.end(), Y[i] + hor + 1) - ys.begin() - 1;
	}
	int K = ys.size();
	int ml = lower_bound(ys.begin(), ys.end(), mn) - ys.begin();
	for (i = 0; i <= K; i++) st[i].clear(), en[i].clear();
	for (i = 1; i <= N; i++) st[l[i]].push_back(i), en[r[i]].push_back(i);
	multiset<int> s;
	multiset<int> delta;
	for (i = 0; i < K; i++) {
		for (auto v : st[i]) {
			int x = X[v];
			if (s.size()) {
				auto rit = s.upper_bound(x);
				if (rit == s.end()) delta.insert(x - *s.rbegin());
				else if (rit == s.begin()) delta.insert(*s.begin() - x);
				else {
					auto lit = prev(rit);
					delta.erase(delta.find(*rit - *lit));
					delta.insert(*rit - x);
					delta.insert(x - *lit);
				}
			}
			s.insert(x);
		}
		if (s.empty()) lims[i] = R + C + 100, limu[i] = limd[i] = 0;
		else {
			lims[i] = 0;
			limu[i] = *s.begin() - 1;
			limd[i] = R - *s.rbegin();
		}
		if (delta.size()) lims[i] = *delta.rbegin() - 1;
		for (auto v : en[i]) {
			int x = X[v];
			s.erase(s.find(x));
			if (s.size()) {
				auto rit = s.upper_bound(x);
				if (rit == s.end()) delta.erase(delta.find(x - *s.rbegin()));
				else if (rit == s.begin()) delta.erase(delta.find((*s.begin() - x)));
				else {
					auto lit = prev(rit);
					delta.insert(*rit - *lit);
					delta.erase(delta.find((*rit - x)));
					delta.erase(delta.find((x - *lit)));
				}
			}
		}
	}
	int j = -1;
	int sum = 0;
	priority_queue<pii> ud, su;
	int ans = 2e9;
	for (i = 0; i < K - 1; i++) {
		ud.emplace(limu[i] + limd[i], i);
		su.emplace(lims[i], i);
		while (j + 1 < i && ys[i + 1] - 1 - ys[j + 1] >= C && j + 1 < ml) j++;
		while (ud.size() && ud.top().second <= j) ud.pop();
		while (su.size() && su.top().second <= j) su.pop();
		if (ys[i + 1] - 1 - ((!~j) ? 0 : ys[j]) >= C) ans = min(ans, max(ud.top().first, su.top().first));
	}
	if (ans > R) return 2e9;
	return ans + hor;
}
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	cin >> R >> C >> N;
	vector<int> v;
	int i, j;
	mn = C;
	for (i = 1; i <= N; i++) cin >> X[i] >> Y[i], mn = min(mn, Y[i]);
	mn--;
	for (i = 1; i <= N; i++) Y[i] -= mn;
	mn++;
	for (i = 0; i <= C; i++) v.push_back(i);
	/*for (i = 1; i <= N; i++) for (j = 1; j <= N; j++) v.push_back(max(0, abs(Y[i] - Y[j]) - 1)), v.push_back(Y[i] - 1 + C - Y[j]);
	sort(v.begin(), v.end());
	v.erase(unique(v.begin(), v.end()), v.end());
	while (v.back() >= C) v.pop_back();
	*/
	int ans = R + C;
	for (auto h : v) ans = min(ans, chk(h));
	cout << ans << ln;
}

Compilation message (stderr)

cultivation.cpp: In function 'int chk(int)':
cultivation.cpp:90:6: warning: unused variable 'sum' [-Wunused-variable]
   90 |  int sum = 0;
      |      ^~~
cultivation.cpp: In function 'int main()':
cultivation.cpp:108:9: warning: unused variable 'j' [-Wunused-variable]
  108 |  int i, j;
      |         ^

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 30
• Subtask 5: 0 / 20
• Subtask 6: 0 / 20