Submission #452092

#	Time	Username	Problem	Language	Result	Execution time	Memory
452092		rainboy	Comparing Plants (IOI20_plants)	C++17	0 / 100	1 ms	384 KiB

plants

#include "plants.h"
#include <stdlib.h>
#include <string.h>

using namespace std;

typedef vector<int> vi;

const int N = 200000, N_ = 1 << 18, INF = 0x3f3f3f3f;

int max(int a, int b) { return a > b ? a : b; }

int pp[N], hh[N], n, k;

int st[N_ * 2], lz[N_ * 2], first[N_ * 2], last[N_ * 2], gap[N_ * 2], n_;

void put(int i, int x) {
	st[i] += x, lz[i] += x;
}

void pul(int i) {
	int l = i << 1, r = l | 1;

	if (st[l] < st[r])
		st[i] = st[l], first[i] = first[l], last[i] = last[l], gap[i] = gap[l];
	else if (st[l] > st[r])
		st[i] = st[r], first[i] = first[r], last[i] = last[r], gap[i] = gap[r];
	else
		st[i] = st[l], first[i] = first[l], last[i] = last[r], gap[i] = max(max(gap[l], gap[r]), first[r] == first[r] - last[l]);
	st[i] += lz[i];
}

void pull(int i) {
	while (i > 1)
		pul(i >>= 1);
}

void build(vi aa, int n) {
	int i;

	n_ = 1;
	while (n_ < n)
		n_ <<= 1;
	memset(lz, 0, n_ * 2 * sizeof *lz);
	for (i = 0; i < n_; i++) {
		st[n_ + i] = i < n ? aa[i] : INF, gap[n_ + i] = 0;
		first[n_ + i] = last[n_ + i] = i;
	}
	for (i = n_ - 1; i > 0; i--)
		pul(i);
}

void update(int l, int r, int x) {
	int l_ = l += n_, r_ = r += n_;

	for ( ; l <= r; l >>= 1, r >>= 1) {
		if ((l & 1) == 1)
			put(l++, x);
		if ((r & 1) == 0)
			put(r--, x);
	}
	pull(l_), pull(r_);
}

int get(int k) {
	int i = 1;

	if (gap[1] < k)
		return first[1];
	while (i < n_)
		if (st[i] == st[i << 1 | 0] + lz[i] && gap[i << 1 | 0] >= k)
			i = i << 1 | 0;
		else if (st[i] == st[i << 1 | 1] + lz[i] && gap[i << 1 | 1] >= k)
			i = i << 1 | 1;
		else
			return first[i << 1 | 1];
	return -1;
}

int next(int l) {
	int i = 1;

	if (l >= last[1])
		return first[1];
	while (i < n_)
		if (st[i] == st[i << 1 | 0] + lz[i] && l < last[i << 1 | 0])
			i = i << 1 | 0;
		else
			i = i << 1 | 1;
	return i - n_;
}

int prev(int r) {
	int i = 1;

	if (r <= first[1])
		return last[1];
	while (i < n_)
		if (st[i] == st[i << 1 | 1] + lz[i] && r > first[i << 1 | 1])
			i = i << 1 | 1;
		else
			i = i << 1 | 0;
	return i - n_;
}

int *ej[N], eo[N];

void append(int i, int j) {
	int o = eo[i]++;

	if (o >= 2 && (o & o - 1) == 0)
		ej[i] = (int *) realloc(ej[i], o * 2 * sizeof *ej[i]);
	ej[i][o] = j;
}

char root[N]; int ta[N], tb[N];

void dfs(int p, int i) {
	static int time;
	int o;

	ta[i] = time++;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p)
			dfs(i, j);
	}
	tb[i] = time;
}

void init(int k_, vi rr) {
	int h, i;

	n = rr.size(), k = k_;
	build(rr, n);
	for (i = 0; i < n; i++)
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
	memset(root, 1, n * sizeof *root);
	for (h = n - 1; h >= 0; h--) {
		int p, q;

		i = get(k);
		update(i, i, INF);
		if (i >= k - 1)
			update(i - k + 1, i, -1);
		else
			update(0, i, -1), update(i - k + 1 + n, n - 1, -1);
		if (h > 0) {
			q = next(i), p = prev(q);
			if (q == p || (q - p + n) % n >= k)
				append(q, i), root[i] = 0;
			q = next((i - k + n) % n), p = prev(q);
			if ((i - q + n) % n < k && (q == p || (q - p + n) % n >= k))
				append(q, i), root[i] = 0;
		}
	}
	for (i = 0; i < n; i++)
		if (root[i])
			dfs(-1, i);
}

int compare_plants(int x, int y) {
	if (ta[x] <= ta[y] && ta[y] < tb[x])
		return -1;
	else if (ta[y] <= ta[x] && ta[x] < tb[y])
		return 1;
	else
		return 0;
}

Compilation message (stderr)

plants.cpp: In function 'void append(int, int)':
plants.cpp:111:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
  111 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 13
• Subtask 4: 0 / 17
• Subtask 5: 0 / 11
• Subtask 6: 0 / 15
• Subtask 7: 0 / 25