Submission #706817

#	Time	Username	Problem	Language	Result	Execution time	Memory
706817		rainboy	Drawing (CEOI22_drawing)	C11	100 / 100	303 ms	38988 KiB

Main

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

#define N	200000

unsigned int X = 12345;

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

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;
}

int xx[N], yy[N];

long long cross(int i, int j, int k) {
	return (long long) (xx[j] - xx[i]) * (yy[k] - yy[i]) - (long long) (xx[k] - xx[i]) * (yy[j] - yy[i]);
}

int i1;

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) {
			long long c = cross(i1, ii[j], i_);

			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;
	}
}

int sz[N];

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

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

		if (j != p) {
			dfs1(i, j);
			sz[i] += sz[j];
		}
	}
}

int ii_[N];

void dfs2(int *ii, int p, int i) {
	int o, s;

	ii_[i] = ii[0];
	s = 1;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p)
			dfs2(ii + s, i, j), s += sz[j];
	}
}

int main() {
	static int ii[N];
	int n, h, i, j;

	scanf("%d", &n);
	for (i = 0; i < n; i++)
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
	for (h = 0; h < n - 1; h++) {
		scanf("%d%d", &i, &j), i--, j--;
		append(i, j), append(j, i);
	}
	for (i = 0; i < n; i++)
		scanf("%d%d", &xx[i], &yy[i]);
	dfs1(-1, 0);
	for (i = 0; i < n; i++)
		ii[i] = i;
	i1 = -1;
	for (i = 0; i < n; i++)
		if (i1 == -1 || xx[i1] > xx[i] || xx[i1] == xx[i] && yy[i1] > yy[i])
			i1 = i;
	ii[0] = i1, ii[i1] = 0;
	sort(ii, 1, n);
	dfs2(ii, -1, 0);
	for (i = 0; i < n; i++)
		printf("%d ", ii_[i] + 1);
	printf("\n");
	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:101:53: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  101 |   if (i1 == -1 || xx[i1] > xx[i] || xx[i1] == xx[i] && yy[i1] > yy[i])
      |                                     ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
Main.c:87:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
Main.c:91:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   91 |   scanf("%d%d", &i, &j), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~
Main.c:95:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   95 |   scanf("%d%d", &xx[i], &yy[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 35 / 35
• Subtask 5: 25 / 25