Submission #1060236

#	Time	Username	Problem	Language	Result	Execution time	Memory
1060236		rainboy	Petrol stations (CEOI24_stations)	C11	100 / 100	285 ms	15444 KiB

Main

#include <stdio.h>
#include <stdlib.h>

#define N	70000

unsigned int Z = 12345;

int rand_() {
	return (Z *= 3) >> 1;
}

int *ej[N], *ew[N], eo[N], n, d_;

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

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

void detach(int i, int j) {
	int o;

	for (o = eo[i]; o--; )
		if (ej[i][o] == j) {
			eo[i]--, ej[i][o] = ej[i][eo[i]], ew[i][o] = ew[i][eo[i]];
			return;
		}
}

int sz[N], n_, c;

void dfs1(int p, int i) {
	int o, centroid;

	sz[i] = 1, centroid = 1;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p) {
			dfs1(i, j);
			sz[i] += sz[j];
			if (sz[j] * 2 > n_)
				centroid = 0;
		}
	}
	if ((n_ - sz[i]) * 2 > n_)
		centroid = 0;
	if (centroid)
		c = i;
}

int ii[N], qu[N], cnt;
int pp[N], rr[N]; long long dd[N]; int kk[N];

void dfs2(int p, int i, int r, long long d) {
	int o, h, lower, upper;

	qu[cnt++] = i;
	ii[n_++] = i;
	pp[i] = p, rr[i] = r, dd[i] = d, sz[i] = 1, kk[i] = 1;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o], w = ew[i][o];

		if (j != p) {
			dfs2(i, j, p == -1 ? j : r, d + w);
			sz[i] += sz[j];
		}
	}
	lower = -1, upper = cnt - 1;
	while (upper - lower > 1) {
		h = (lower + upper) / 2;
		if (dd[i] - dd[qu[h]] > d_)
			lower = h;
		else
			upper = h;
	}
	if (lower != -1)
		kk[qu[upper]] += kk[i];
	cnt--;
}

void sort(int *ii, int l, int r) {
	while (l < r) {
		int i = l, j = l, k = r, i_ = ii[l + rand_() % (r - l)], tmp;

		while (j < k) {
			int c = dd[ii[j]] != dd[i_] ? (dd[ii[j]] < dd[i_] ? -1 : 1) : sz[i_] - sz[ii[j]];

			if (c == 0)
				j++;
			else if (c < 0) {
				tmp = ii[i], ii[i] = ii[j], ii[j] = tmp;
				i++, j++;
			} else {
				k--;
				tmp = ii[j], ii[j] = ii[k], ii[k] = tmp;
			}
		}
		sort(ii, l, i);
		l = k;
	}
}

long long ans[N]; int kk_[N], ss[N];

void dfs3(int p, int i) {
	int o, h, lower, upper;

	qu[cnt++] = i;
	lower = -1, upper = cnt - 1;
	while (upper - lower > 1) {
		h = (lower + upper) / 2;
		if (dd[i] - dd[qu[h]] > d_)
			lower = h;
		else
			upper = h;
	}
	kk_[i] += ss[qu[upper]];
	ss[i] = (p == -1 ? 0 : ss[p]) + kk_[i];
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p)
			kk_[j] -= ss[qu[upper]], dfs3(i, j);
	}
	if (p != -1)
		ans[p] += (long long) kk_[i] * sz[i];
	cnt--;
}

void cd(int n, int i) {
	static int kk1[N];
	int r, h, h1, h2, j, o, k;

	n_ = n, dfs1(-1, i), r = c;
	n_ = 0, dfs2(-1, r, r, 0);
	for (h = 1; h < n; h++) {
		i = ii[h];
		ans[i] += (long long) (kk[i] - 1) * (n - sz[rr[i]]);
	}
	sort(ii, 0, n);
	kk1[r] = 0;
	for (o = eo[r]; o--; ) {
		i = ej[r][o];
		kk1[i] = 0;
	}
	for (h1 = 0, h2 = n - 1, k = 0; h1 < n; h1++) {
		i = ii[h1];
		while (h2 >= 0 && dd[i] + dd[j = ii[h2]] > d_) {
			if (dd[j] <= d_)
				k += kk[j], kk1[rr[j]] += kk[j];
			h2--;
		}
		kk_[i] = k - kk1[rr[i]];
	}
	for (h = n - 1; h > 0; h--) {
		i = ii[h];
		kk_[i] -= kk_[pp[i]];
	}
	dfs3(-1, r);
	for (o = eo[r]; o--; ) {
		i = ej[r][o];
		detach(i, r), cd(sz[i], i);
	}
}

int main() {
	int h, i, j, w;

	scanf("%d%d", &n, &d_);
	for (i = 0; i < n; i++) {
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
		ew[i] = (int *) malloc(2 * sizeof *ew[i]);
	}
	for (h = 0; h < n - 1; h++) {
		scanf("%d%d%d", &i, &j, &w);
		append(i, j, w), append(j, i, w);
	}
	cd(n, 0);
	for (i = 0; i < n; i++)
		printf("%lld\n", ans[i]);
	return 0;
}

Compilation message (stderr)

Main.c: In function 'append':
Main.c:17:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   17 |  if (o >= 2 && (o & o - 1) == 0) {
      |                     ~~^~~
Main.c: In function 'main':
Main.c:174:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  174 |  scanf("%d%d", &n, &d_);
      |  ^~~~~~~~~~~~~~~~~~~~~~
Main.c:180:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  180 |   scanf("%d%d%d", &i, &j, &w);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 18 / 18
• Subtask 2: 8 / 8
• Subtask 3: 10 / 10
• Subtask 4: 12 / 12
• Subtask 5: 17 / 17
• Subtask 6: 35 / 35