Submission #485891

#	Time	Username	Problem	Language	Result	Execution time	Memory
485891		rainboy	ČVENK (COI15_cvenk)	C11	22 / 100	26 ms	1528 KiB

cvenk

#include <stdio.h>

#define N	100000
#define X	512
#define L	29

int kk[X][X], n, x_, y_;

int dfs1(int x, int y) {
	int k, k1, k2;

	if (x >= X || y >= X || (x & y) != 0)
		return 0;
	k1 = dfs1(x, y + 1), k2 = dfs1(x + 1, y), k = kk[x][y] + k1 + k2;
	if (k1 * 2 <= n && k2 * 2 <= n && (n - k) * 2 <= n)
		x_ = x, y_ = y;
	return k;
}

long long ans;

void lca(int x1, int y1, int x2, int y2, int *x, int *y, int l) {
	if (l == 0)
		*x = 0, *y = 0;
	else {
		int n = 1 << l - 1;

		if (x1 >= n && y1 < n && x2 >= n && y2 < n)
			lca(x1 - n, y1, x2 - n, y2, x, y, l - 1), *x += n;
		else if (x1 < n && y1 >= n && x2 < n && y2 >= n)
			lca(x1, y1 - n, x2, y2 - n, x, y, l - 1), *y += n;
		else {
			if (x1 >= n && y1 < n)
				x1 = n - 1, y1 = 0;
			else if (x1 < n && y1 >= n)
				x1 = 0, y1 = n - 1;
			if (x2 >= n && y2 < n)
				x2 = n - 1, y2 = 0;
			else if (x2 < n && y2 >= n)
				x2 = 0, y2 = n - 1;
			lca(x1, y1, x2, y2, x, y, l - 1);
		}
	}
}

long long dist(int x1, int y1, int x2, int y2) {
	int x, y;

	lca(x1, y1, x2, y2, &x, &y, L - 1);
	return (long long) (x1 + y1) + (x2 + y2) - (long long) (x + y) * 2;
}

int main() {
	static int xx[N], yy[N];
	int i;

	scanf("%d", &n);
	if (n == 2) {
		scanf("%d%d%d%d", &xx[0], &yy[0], &xx[1], &yy[1]);
		printf("%lld\n", dist(xx[0], yy[0], xx[1], yy[1]));
		return 0;
	}
	for (i = 0; i < n; i++) {
		scanf("%d%d", &xx[i], &yy[i]);
		kk[xx[i]][yy[i]]++;
	}
	dfs1(0, 0);
	ans = 0;
	for (i = 0; i < n; i++)
		ans += dist(xx[i], yy[i], x_, y_);
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

cvenk.c: In function 'lca':
cvenk.c:26:18: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   26 |   int n = 1 << l - 1;
      |                ~~^~~
cvenk.c: In function 'main':
cvenk.c:57:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   57 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
cvenk.c:59:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |   scanf("%d%d%d%d", &xx[0], &yy[0], &xx[1], &yy[1]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cvenk.c:64:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |   scanf("%d%d", &xx[i], &yy[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 17
• Subtask 2: 0 / 21
• Subtask 3: 22 / 22
• Subtask 4: 0 / 40