Submission #488548

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
488548	2021-11-19T15:03:47 Z	rainboy	Logičari (COCI21_logicari)	C	110 / 110	53 ms	8136 KB

Main

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

#define N	100000
#define INF	0x3f3f3f3f

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

int *ej[N], eo[N], dd[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 dp[N][2][2];

void dfs(int i) {
	int o, c, d;

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

			if (dd[j] != -1) {
				for (c = 0; c < 2; c++)
					for (d = 1; d >= 0; d--) {
						int x = INF;

						if (dp[i][0][1 - c] != INF)
							x = min(x, dp[j][c][d] + dp[i][0][1 - c]);
						if (d == 1 && dp[i][1][1 - c] != INF)
							x = min(x, dp[j][c][0] + dp[i][1][1 - c]);
						dp[j][c][d] = x;
					}
				dd[j]++, dfs(j);
				break;
			}
		}
	}
}

int main() {
	static int qu[N], dp_[2][2][2][2], dq_[2][2][2][2];
	int n, h, i, j, o, cnt, c1, d1, c2, d2, c3, d3, ans;

	scanf("%d", &n);
	if (n > N) {
		printf("%d\n", n % 4 == 0 ? n / 2 : -1);
		return 0;
	}
	for (i = 0; i < n; i++)
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
	for (h = 0; h < n; h++) {
		scanf("%d%d", &i, &j), i--, j--;
		append(i, j), append(j, i);
	}
	for (i = 0; i < n; i++)
		dp[i][0][0] = 0, dp[i][0][1] = INF, dp[i][1][0] = 1, dp[i][1][1] = INF;
	for (i = 0; i < n; i++)
		dfs(i);
	for (i = 0; i < n; i++)
		if (dd[i] != -1)
			break;
	cnt = 0;
	while (dd[i] != -1) {
		dd[i] = -1, qu[cnt++] = i;
		for (o = eo[i]; o--; ) {
			j = ej[i][o];
			if (dd[j] != -1) {
				i = j;
				break;
			}
		}
	}
	for (c1 = 0; c1 < 2; c1++)
		for (d1 = 0; d1 < 2; d1++)
			for (c2 = 0; c2 < 2; c2++)
				for (d2 = 0; d2 < 2; d2++)
					dp_[c1][d1][c2][d2] = INF;
	for (c1 = 0; c1 < 2; c1++)
		for (d1 = 0; d1 < 2; d1++)
			for (c2 = 0; c2 < 2; c2++)
				for (d2 = 0; d2 < 2; d2++) {
					if (d1 + c2 > 1 || d2 + c1 > 1)
						continue;
					dp_[c1][d1 + c2][c2][d2 + c1] = min(dp_[c1][d1 + c2][c2][d2 + c1], dp[qu[0]][c1][d1] + dp[qu[1]][c2][d2]);
				}
	for (h = 2; h < cnt; h++) {
		i = qu[h];
		for (c1 = 0; c1 < 2; c1++)
			for (d1 = 0; d1 < 2; d1++)
				for (c2 = 0; c2 < 2; c2++)
					for (d2 = 0; d2 < 2; d2++)
						dq_[c1][d1][c2][d2] = INF;
		for (c1 = 0; c1 < 2; c1++)
			for (d1 = 0; d1 < 2; d1++)
				for (c2 = 0; c2 < 2; c2++)
					for (d2 = 0; d2 < 2; d2++) {
						int x = dp_[c1][d1][c2][d2];

						if (x == INF)
							continue;
						for (c3 = 0; c3 < 2; c3++)
							for (d3 = 0; d3 < 2; d3++) {
								int y = dp[i][c3][d3];

								if (d2 + c3 != 1 || d3 + c2 > 1 || y == INF)
									continue;
								dq_[c1][d1][c3][d3 + c2] = min(dq_[c1][d1][c3][d3 + c2], x + y);
							}
					}
		for (c1 = 0; c1 < 2; c1++)
			for (d1 = 0; d1 < 2; d1++)
				for (c2 = 0; c2 < 2; c2++)
					for (d2 = 0; d2 < 2; d2++)
						dp_[c1][d1][c2][d2] = dq_[c1][d1][c2][d2];
	}
	ans = INF;
	for (c1 = 0; c1 < 2; c1++)
		for (d1 = 0; d1 < 2; d1++)
			for (c2 = 0; c2 < 2; c2++)
				for (d2 = 0; d2 < 2; d2++)
					if (d1 + c2 == 1 && d2 + c1 == 1)
						ans = min(ans, dp_[c1][d1][c2][d2]);
	if (ans == INF)
		ans = -1;
	printf("%d\n", ans);
	return 0;
}

Compilation message

Main.c: In function 'append':
Main.c:14:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   14 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~
Main.c: In function 'main':
Main.c:51:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
Main.c:59:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |   scanf("%d%d", &i, &j), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~

Subtask #1

10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	42 ms	7976 KB	Output is correct
6	Correct	49 ms	7968 KB	Output is correct
7	Correct	53 ms	8100 KB	Output is correct
8	Correct	53 ms	7984 KB	Output is correct

Subtask #2

10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	0 ms	204 KB	Output is correct
6	Correct	0 ms	204 KB	Output is correct
7	Correct	1 ms	204 KB	Output is correct
8	Correct	0 ms	204 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Correct	0 ms	204 KB	Output is correct
11	Correct	0 ms	204 KB	Output is correct
12	Correct	0 ms	204 KB	Output is correct

Subtask #3

40.0 / 40.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	0 ms	204 KB	Output is correct
6	Correct	0 ms	204 KB	Output is correct
7	Correct	1 ms	204 KB	Output is correct
8	Correct	0 ms	204 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Correct	0 ms	204 KB	Output is correct
11	Correct	0 ms	204 KB	Output is correct
12	Correct	0 ms	204 KB	Output is correct
13	Correct	0 ms	332 KB	Output is correct
14	Correct	1 ms	332 KB	Output is correct
15	Correct	0 ms	332 KB	Output is correct
16	Correct	0 ms	332 KB	Output is correct
17	Correct	0 ms	324 KB	Output is correct
18	Correct	1 ms	332 KB	Output is correct
19	Correct	0 ms	204 KB	Output is correct
20	Correct	1 ms	332 KB	Output is correct
21	Correct	1 ms	332 KB	Output is correct
22	Correct	1 ms	332 KB	Output is correct
23	Correct	1 ms	332 KB	Output is correct
24	Correct	0 ms	332 KB	Output is correct

Subtask #4

50.0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	204 KB	Output is correct
2	Correct	0 ms	204 KB	Output is correct
3	Correct	0 ms	204 KB	Output is correct
4	Correct	0 ms	204 KB	Output is correct
5	Correct	42 ms	7976 KB	Output is correct
6	Correct	49 ms	7968 KB	Output is correct
7	Correct	53 ms	8100 KB	Output is correct
8	Correct	53 ms	7984 KB	Output is correct
9	Correct	0 ms	204 KB	Output is correct
10	Correct	0 ms	204 KB	Output is correct
11	Correct	0 ms	204 KB	Output is correct
12	Correct	0 ms	204 KB	Output is correct
13	Correct	0 ms	204 KB	Output is correct
14	Correct	0 ms	204 KB	Output is correct
15	Correct	1 ms	204 KB	Output is correct
16	Correct	0 ms	204 KB	Output is correct
17	Correct	0 ms	204 KB	Output is correct
18	Correct	0 ms	204 KB	Output is correct
19	Correct	0 ms	204 KB	Output is correct
20	Correct	0 ms	204 KB	Output is correct
21	Correct	0 ms	332 KB	Output is correct
22	Correct	1 ms	332 KB	Output is correct
23	Correct	0 ms	332 KB	Output is correct
24	Correct	0 ms	332 KB	Output is correct
25	Correct	0 ms	324 KB	Output is correct
26	Correct	1 ms	332 KB	Output is correct
27	Correct	0 ms	204 KB	Output is correct
28	Correct	1 ms	332 KB	Output is correct
29	Correct	1 ms	332 KB	Output is correct
30	Correct	1 ms	332 KB	Output is correct
31	Correct	1 ms	332 KB	Output is correct
32	Correct	0 ms	332 KB	Output is correct
33	Correct	40 ms	6904 KB	Output is correct
34	Correct	37 ms	6856 KB	Output is correct
35	Correct	34 ms	6952 KB	Output is correct
36	Correct	42 ms	6860 KB	Output is correct
37	Correct	8 ms	2000 KB	Output is correct
38	Correct	43 ms	7116 KB	Output is correct
39	Correct	3 ms	848 KB	Output is correct
40	Correct	43 ms	7116 KB	Output is correct
41	Correct	35 ms	8068 KB	Output is correct
42	Correct	47 ms	8136 KB	Output is correct
43	Correct	36 ms	7632 KB	Output is correct
44	Correct	34 ms	7924 KB	Output is correct