Submission #482426

#	Time	Username	Problem	Language	Result	Execution time	Memory
482426		rainboy	Papričice (COCI20_papricice)	C11	50 / 110	1084 ms	12884 KiB

papricice

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

#define N	200000

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

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 ta[N], tb[N], sz[N];

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

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

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

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

	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);
	}
	dfs(-1, 0);
	ans = n + 1;
	for (i = 1; i < n; i++)
		for (j = i + 1; j < n; j++) {
			int a, b, c;

			if (ta[i] <= ta[j] && ta[j] < tb[i])
				a = sz[j], b = sz[i] - sz[j], c = n - sz[i];
			else if (ta[j] <= ta[i] && ta[i] < tb[j])
				a = sz[i], b = sz[j] - sz[i], c = n - sz[j];
			else
				a = sz[i], b = sz[j], c = n - sz[i] - sz[j];
			ans = min(ans, max(max(a, b), c) - min(min(a, b), c));
		}
	printf("%d\n", ans);
	return 0;
}

Compilation message (stderr)

papricice.c: In function 'append':
papricice.c:14:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   14 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~
papricice.c: In function 'main':
papricice.c:41:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
papricice.c:45:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |   scanf("%d%d", &i, &j), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 35 / 35
• Subtask 3: 0 / 60