제출 #491194

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
491194		rainboy	Paint (COI20_paint)	C11	48 / 100	506 ms	11580 KiB

paint

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

#define NM	200000

int aa[NM], n, m;

void dfs(int i, int j, int a, int c) {
	if (i < 0 || i >= n || j < 0 || j >= m || aa[i * m + j] != a)
		return;
	aa[i * m + j] = c;
	dfs(i - 1, j, a, c);
	dfs(i + 1, j, a, c);
	dfs(i, j - 1, a, c);
	dfs(i, j + 1, a, c);
}

int ds[NM], ll[NM], rr[NM];

int find(int i) {
	return ds[i] < 0 ? i : (ds[i] = find(ds[i]));
}

void join(int i, int j) {
	i = find(i);
	j = find(j);
	if (i == j)
		return;
	if (ds[i] > ds[j])
		ds[i] = j, ll[j] = ll[i];
	else {
		if (ds[i] == ds[j])
			ds[i]--;
		ds[j] = i, rr[i] = rr[j];
	}
}

int *ej[NM], eo[NM];

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;
}

void merge(int i1, int i2) {
	int o;

	if (eo[i2] != 0) {
		if (eo[i1] == 0)
			ej[i1] = (int *) malloc(2 * sizeof *ej[i1]);
		for (o = eo[i2]; o--; )
			append(i1, ej[i2][o]);
		free(ej[i2]), eo[i2] = 0;
	}
}

void join_(int i, int j) {
	i = find(i);
	j = find(j);
	if (i == j)
		return;
	if (ds[i] > ds[j]) {
		ds[i] = j;
		merge(j, i);
	} else {
		if (ds[i] == ds[j])
			ds[i]--;
		ds[j] = i;
		merge(i, j);
	}
}

void collapse(int i) {
	static int qu[NM * 4];
	int o, o_;

	if (eo[i] == 0)
		return;
	for (o = eo[i]; o--; )
		qu[o] = ej[i][o];
	o_ = eo[i];
	free(ej[i]), eo[i] = 0;
	for (o = o_; o--; )
		join_(i, qu[o]);
}

int main() {
	int q, i, j;

	scanf("%d%d", &n, &m);
	for (i = 0; i < n; i++)
		for (j = 0; j < m; j++)
			scanf("%d", &aa[i * m + j]);
	scanf("%d", &q);
	if (n == 1) {
		for (j = 0; j < m; j++)
			ds[j] = -1, ll[j] = rr[j] = j;
		for (j = 1; j < m; j++)
			if (aa[j] == aa[j - 1])
				join(j - 1, j);
		while (q--) {
			int a, l, r;

			scanf("%*d%d%d", &j, &a), j--;
			aa[find(j)] = a;
			l = ll[find(j)], r = rr[find(j)];
			if (l > 0 && aa[find(l - 1)] == a)
				join(l - 1, j);
			if (r + 1 < m && aa[find(r + 1)] == a)
				join(j, r + 1);
		}
		for (j = 0; j < m; j++)
			printf("%d ", aa[find(j)]);
		printf("\n");
	} else if (n * m <= 10000) {
		while (q--) {
			int c;

			scanf("%d%d%d", &i, &j, &c), i--, j--;
			if (aa[i * m + j] != c)
				dfs(i, j, aa[i * m + j], c);
		}
		for (i = 0; i < n; i++) {
			for (j = 0; j < m; j++)
				printf("%d ", aa[i * m + j]);
			printf("\n");
		}
	} else {
		memset(ds, -1, n * m * sizeof *ds);
		for (i = 0; i < n * m; i++)
			ej[i] = (int *) malloc(2 * sizeof *ej[i]);
		for (i = 0; i < n; i++)
			for (j = 0; j < m; j++) {
				if (i > 0 && aa[i * m + j] != aa[(i - 1) * m + j])
					append(i * m + j, (i - 1) * m + j), append((i - 1) * m + j, i * m + j);
				if (j > 0 && aa[i * m + j] != aa[i * m + (j - 1)])
					append(i * m + j, i * m + (j - 1)), append(i * m + (j - 1), i * m + j);
			}
		for (i = 0; i < n; i++)
			for (j = 0; j < m; j++) {
				if (i > 0 && aa[i * m + j] == aa[(i - 1) * m + j])
					join_(i * m + j, (i - 1) * m + j);
				if (j > 0 && aa[i * m + j] == aa[i * m + (j - 1)])
					join_(i * m + j, i * m + (j - 1));
			}
		while (q--) {
			int c;

			scanf("%d%d%d", &i, &j, &c), i--, j--;
			i = find(i * m + j);
			if (aa[i] != c) {
				aa[i] = c;
				collapse(i);
			}
		}
		for (i = 0; i < n; i++) {
			for (j = 0; j < m; j++)
				printf("%d ", aa[find(i * m + j)]);
			printf("\n");
		}
	}
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

paint.c: In function 'append':
paint.c:44:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   44 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~
paint.c: In function 'main':
paint.c:94:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   94 |  scanf("%d%d", &n, &m);
      |  ^~~~~~~~~~~~~~~~~~~~~
paint.c:97:4: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   97 |    scanf("%d", &aa[i * m + j]);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
paint.c:98:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   98 |  scanf("%d", &q);
      |  ^~~~~~~~~~~~~~~
paint.c:108:4: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  108 |    scanf("%*d%d%d", &j, &a), j--;
      |    ^~~~~~~~~~~~~~~~~~~~~~~~
paint.c:123:4: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  123 |    scanf("%d%d%d", &i, &j, &c), i--, j--;
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
paint.c:153:4: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  153 |    scanf("%d%d%d", &i, &j, &c), i--, j--;
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 9 / 9
• Subtask 3: 31 / 31
• Subtask 4: 0 / 52