Submission #1055672

#	Time	Username	Problem	Language	Result	Execution time	Memory
1055672		Gromp15	Comparing Plants (IOI20_plants)	C++17	100 / 100	761 ms	85420 KiB

plants

#include <bits/stdc++.h>
#define ll long long
#include "plants.h"
#define ar array
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
using namespace std;
template<typename T> bool ckmin(T &a, const T &b) { return a > b ? a = b, 1 : 0; }
template<typename T> bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }

const int INF = 1e9;

struct seg {
	int N; vector<ar<int, 2>> tree; vector<int> lazy;
	void pull(int node) {
		tree[node] = min(tree[node*2], tree[node*2+1]);
	}
	void push(int node) {
		if (!lazy[node]) return;
		tree[node][0] += lazy[node];
		if (node < N) lazy[node*2] += lazy[node], lazy[node*2+1] += lazy[node];
		lazy[node] = 0;
	}
	seg(int n, const vector<int>& r) : N(1<<(__lg(n)+1)), tree(2*N), lazy(2*N) {
		for (int i = 0; i < n; i++) tree[i+N] = {r[i], i};
		for (int i = N-1; i >= 1; i--) pull(i);
	}
	ar<int, 2> query(int node, int nl, int nr, int ql, int qr) {
		push(node);
		if (ql > nr || qr < nl) return {INF};
		if (ql <= nl && nr <= qr) return tree[node];
		int mid = (nl+nr)/2;
		return min(query(node*2, nl, mid, ql, qr), query(node*2+1, mid+1, nr, ql, qr));
	}
	void update(int node, int nl, int nr, int ql, int qr, int v) {
		push(node);
		if (ql > nr || qr < nl) return;
		if (ql <= nl && nr <= qr) {
			lazy[node] += v; push(node); return;
		}
		int mid = (nl+nr)/2;
		update(node*2, nl, mid, ql, qr, v), update(node*2+1, mid+1, nr, ql, qr, v);
		pull(node);
	}
};

struct seg2 {
	int N; vector<ar<int, 2>> tree;
	seg2(int n) : N(1<<(__lg(n)+1)), tree(2*N, {INF}) {}
	void update(int pos, ar<int, 2> nw) {
		for (int i = pos + N; i; i >>= 1) ckmin(tree[i], nw);
	}
	ar<int, 2> query(int node, int nl, int nr, int ql, int qr) {
		if (ql > nr || qr < nl) return {INF};
		if (ql <= nl && nr <= qr) return tree[node];
		int mid = (nl+nr)/2;
		return min(query(node*2, nl, mid, ql, qr), query(node*2+1, mid+1, nr, ql, qr));
	}
};

const int LOG = 19;

int n, k;
vector<int> got;
vector<vector<int>> toL, toR;

int dist(int x) {
	return x < 0 ? x + n : x;
}

void init(int _k, std::vector<int> r) {
	k = _k;
	n = sz(r);
	seg st(n, r);
	got.resize(n);
	set<int> in;
	set<ar<int, 2>> where;
	auto add = [&](int pos) {
		//cout << "Add " << pos << endl;
		assert(!in.count(pos));
		if (in.size() > 1) {
			auto it = in.lower_bound(pos);
			int R = it != in.end() ? *it : *in.begin();
			int L = it != in.begin() ? *prev(it) : *prev(in.end());
			assert(where.count({dist(R - L), R}));
			where.erase({dist(R - L), R});
			where.insert({dist(R - pos), R});
			where.insert({dist(pos - L), pos});
		}
		else if (in.size() == 1) {
			int other = *in.begin();
			assert(where.size() == 1);
			assert((*where.begin())[0] == n);
			where.erase(where.begin());
			where.insert({dist(other - pos), other});
			where.insert({dist(pos - other), pos});
		}
		else {
			where.insert({n, pos});
		}
		in.insert(pos);
	};
	auto rem = [&](int pos) {
		//cout << "Rem " << pos << endl;
		assert(in.count(pos));
		if (in.size() == 1) {
			in.erase(in.begin());
			where.erase(where.begin());
		}
		else if (in.size() == 2) {
			int other = *in.begin() == pos ? *next(in.begin()) : *in.begin();
			assert(where.count({dist(pos - other), pos}));
			in.erase(pos);
			where.erase(where.begin());
			where.erase(where.begin());
			where.insert({n, other});
		}
		else {
			auto it = in.upper_bound(pos);
			int R = it != in.end() ? *it : *in.begin();
			auto it2 = in.lower_bound(pos);
			int L = it2 != in.begin() ? *prev(it2) : *prev(in.end());
			assert(where.count({dist(R - pos), R}));
			assert(where.count({dist(pos - L), pos}));
			where.erase({dist(R - pos), R});
			where.erase({dist(pos - L), pos});
			where.insert({dist(R - L), R});
			in.erase(pos);
		}
	};
	int on = n;
	while (1) {
		auto q = st.query(1, 0, st.N-1, 0, n-1);
		if (!q[0]) { 
			add(q[1]);
			st.update(1, 0, st.N-1, q[1], q[1], INF);
		}
		else {
			if (where.empty()) break;
			auto [val, pos] = *prev(where.end());
			assert(val >= k);
			rem(pos);
			got[pos] = on--;
			int L = pos - k + 1, R = pos - 1;
			if (L < 0) L += n;
			if (R < 0) R += n;
			if (L <= R) st.update(1, 0, st.N-1, L, R, -1);
			else {
				st.update(1, 0, st.N-1, 0, R, -1);
				st.update(1, 0, st.N-1, L, n-1, -1);
			}
		}
	}
	toL.resize(LOG, vector<int>(2 * n, 2 * n));
	toR.resize(LOG, vector<int>(2 * n, -1));
	vector<int> idx(n);
	iota(all(idx), 0);
	sort(all(idx), [&](int x, int y) { return got[x] > got[y]; });
	seg2 st2(2 * n);
	auto query = [&](int l, int r) {
		return st2.query(1, 0, st2.N-1, max(0, l), min(2*n-1, r));
	};
	for (int i = 0; i < n; i++) {
		int pos = idx[i];
		for (int d : {0, n}) {
			auto l = query(pos + d - k + 1, pos + d - 1);
			toL[0][pos + d] = l[0] == INF ? 2 * n : l[1];
			auto r = query(pos + d + 1, pos + d + k - 1);
			toR[0][pos + d] = r[0] == INF ? -1 : r[1];
			st2.update(pos, ar<int, 2>{got[pos], pos});
			st2.update(pos + d, ar<int, 2>{got[pos], pos + d});
		}
	}
	for (int i = 1; i < LOG; i++) {
		for (int j = 0; j < 2 * n; j++) {
			toL[i][j] = toL[i-1][j] < 2 * n ? toL[i-1][toL[i-1][j]] : 2 * n;
			toR[i][j] = ~toR[i-1][j] ? toR[i-1][toR[i-1][j]] : -1;
		}
	}
}

bool win_left(int x, int y) {
	if (x >= y) {
		for (int i = LOG-1; i >= 0; i--) if (toL[i][x] < 2 * n && toL[i][x] >= y + (k - 1)) x = toL[i][x];
		if (x <= y + (k - 1) && got[x % n] <= got[y % n]) return 1;
		x = toL[0][x];
		return x < 2 * n && x >= y - (k - 1) && got[x % n] <= got[y % n];
	}
	else {
		x += n;
		for (int i = LOG-1; i >= 0; i--) if (toL[i][x] < 2 * n && toL[i][x] >= y + (k - 1)) x = toL[i][x];
		if (x <= y + (k - 1) && got[x % n] <= got[y % n]) return 1;
		x = toL[0][x];
		return x < 2 * n && x >= y - (k - 1) && got[x % n] <= got[y % n];
	}
}
bool win_right(int x, int y) {
	if (x <= y) {
		for (int i = LOG-1; i >= 0; i--) if (~toR[i][x] && toR[i][x] <= y - (k - 1)) x = toR[i][x];
		if (x >= y - (k - 1) && got[x % n] <= got[y % n]) return 1;
		x = toR[0][x];
		return ~x && x <= y + k - 1 && got[x % n] <= got[y % n];
	}
	else {
		y += n;
		for (int i = LOG-1; i >= 0;  i--) if (~toR[i][x] && toR[i][x] <= y - (k - 1)) x = toR[i][x];
		if (x >= y - (k - 1) && got[x % n] <= got[y % n]) return 1;
		x = toR[0][x];
		return ~x && x <= y + k - 1 && got[x % n] <= got[y % n];
	}
}

bool win(int x, int y) {
	return win_left(x, y) || win_right(x, y);
}

int compare_plants(int x, int y) {
	int w1 = win(x, y), w2 = win(y, x);
	return (!w1 && !w2) || (w1 && w2) ? 0 : w1 ? -1 : 1;
}

• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 13 / 13
• Subtask 4: 17 / 17
• Subtask 5: 11 / 11
• Subtask 6: 15 / 15
• Subtask 7: 25 / 25