Submission #544773

#	Time	Username	Problem	Language	Result	Execution time	Memory
544773		rainboy	Harbingers (CEOI09_harbingers)	C11	100 / 100	184 ms	28988 KiB

harbingers

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

#define N	100000
#define LN	16	/* LN = floor(log2(N - 1)) */

int min(int a, int b) { return a < b ? a : b; }

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

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;
}

int pp[N][LN + 1], dd[N], ss[N], vv[N]; long long xx[N], yy[N];

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

void dfs(int p, int i, int d, long long x) {
	int o, h;

	dd[i] = d, xx[i] = x;
	if (i > 0) {
		int j;

		for (h = LN, j = p; h >= 0; h--) {
			int j_ = pp[j][h];

			if (j_ != -1 && pp[j_][0] != -1 && yy[j_] + (xx[i] - xx[j_]) * vv[i] >= yy[pp[j_][0]] + (xx[i] - xx[pp[j_][0]]) * vv[i])
				j = j_;
		}
		if (pp[j][0] != -1 && yy[j] + (xx[i] - xx[j]) * vv[i] >= yy[pp[j][0]] + (xx[i] - xx[pp[j][0]]) * vv[i])
			j = pp[j][0];
		yy[i] = yy[j] + (xx[i] - xx[j]) * vv[i] + ss[i];
		for (h = LN, j = p; h >= 0; h--) {
			int j_ = pp[j][h];

			if (j_ != -1 && pp[j_][0] != -1 && cross(pp[j_][0], j_, i) <= 0)
				j = j_;
		}
		if (j != -1 && pp[j][0] != -1 && cross(pp[j][0], j, i) <= 0)
			j = pp[j][0];
		pp[i][0] = j;
	} else
		pp[i][0] = -1;
	for (h = 0; h < LN; h++)
		pp[i][h + 1] = pp[i][h] == -1 ? -1 : pp[pp[i][h]][h];
	for (o = eo[i]; o--; ) {
		int j = ej[i][o], w = ew[i][o];

		if (j != p)
			dfs(i, j, d + 1, x + w);
	}
}

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

	scanf("%d", &n);
	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++) {
		int w;

		scanf("%d%d%d", &i, &j, &w), i--, j--;
		append(i, j, w), append(j, i, w);
	}
	for (i = 1; i < n; i++)
		scanf("%d%d", &ss[i], &vv[i]);
	dfs(-1, 0, 0, 0);
	for (i = 1; i < n; i++)
		printf("%lld ", yy[i]);
	printf("\n");
	return 0;
}

Compilation message (stderr)

harbingers.c: In function 'append':
harbingers.c:14:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   14 |  if (o >= 2 && (o & o - 1) == 0) {
      |                     ~~^~~
harbingers.c: In function 'main':
harbingers.c:67:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
harbingers.c:75:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |   scanf("%d%d%d", &i, &j, &w), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~
harbingers.c:79:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |   scanf("%d%d", &ss[i], &vv[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 100 / 100