Submission #494167

# Submission time Handle Problem Language Result Execution time Memory
494167 2021-12-14T14:00:54 Z rainboy Newspapers (CEOI21_newspapers) C
50 / 100
2 ms 360 KB
/* https://csacademy.com/contest/archive/task/catch-the-thief */
#include <stdio.h>
#include <stdlib.h>

#define N	1000

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 pp[N], i_, d_;

void dfs1(int p, int i, int d) {
	int o;

	pp[i] = p;
	if (d_ < d)
		i_ = i, d_ = d;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p)
			dfs1(i, j, d + 1);
	}
}

char path[N];

int dfs2(int p, int i, int d) {
	int o;

	if (d >= 3)
		return 0;
	for (o = eo[i]; o--; ) {
		int j = ej[i][o];

		if (j != p && !path[j] && !dfs2(i, j, d + 1))
			return 0;
	}
	return 1;
}

int main() {
	static int qu[N], qu_[N * 5];
	int n, m, h, i, j, u, v, o, cnt;

	scanf("%d%d", &n, &m);
	if (m != n - 1) {
		printf("NO\n");
		return 0;
	}
	if (n == 1) {
		printf("YES\n");
		printf("1\n");
		printf("1\n");
		return 0;
	}
	if (n == 2) {
		printf("YES\n");
		printf("2\n");
		printf("1 1\n");
		return 0;
	}
	for (i = 0; i < n; i++)
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
	for (h = 0; h < m; h++) {
		scanf("%d%d", &i, &j), i--, j--;
		append(i, j), append(j, i);
	}
	i_ = -1, d_ = -1;
	dfs1(-1, 0, 0);
	u = i_;
	i_ = -1, d_ = -1;
	dfs1(-1, u, 0);
	v = i_;
	for (h = d_, i = v; h >= 0; h--, i = pp[i])
		path[qu[h] = i] = 1;
	path[u] = path[v] = 0;
	for (h = 1; h < d_; h++)
		if (!dfs2(-1, qu[h], 0)) {
			printf("NO\n");
			return 0;
		}
	cnt = 0;
	for (h = 1; h < d_; h++) {
		int special1, special2;

		i = qu[h], special1 = special2 = 1;
		for (o = 0; o < eo[i]; o++) {
			j = ej[i][o];
			if (!path[j]) {
				special1 = 0;
				if (eo[j] > 1) {
					special2 = 0;
					qu_[cnt++] = i, qu_[cnt++] = j;
				}
			}
		}
		for (o = eo[i]; o--; ) {
			j = ej[i][o];
			if (!path[j] && eo[j] > 1)
				qu_[cnt++] = j, qu_[cnt++] = i;
		}
		if (special1)
			qu_[cnt++] = i;
		else if (special2)
			qu_[cnt++] = i, qu_[cnt++] = i;
	}
	printf("YES\n");
	printf("%d\n", cnt);
	for (h = 0; h < cnt; h++)
		printf("%d ", qu_[h] + 1);
	printf("\n");
	return 0;
}

Compilation message

newspapers.c: In function 'append':
newspapers.c:12:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   12 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~
newspapers.c: In function 'main':
newspapers.c:53:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   53 |  scanf("%d%d", &n, &m);
      |  ^~~~~~~~~~~~~~~~~~~~~
newspapers.c:73:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |   scanf("%d%d", &i, &j), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~
# 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 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
4 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
5 Correct 0 ms 204 KB Output is correct
6 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
7 Correct 0 ms 204 KB Output is correct
8 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
9 Correct 0 ms 204 KB Output is correct
10 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
11 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
12 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
13 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
14 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
15 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
16 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
17 Partially correct 0 ms 276 KB Failed to provide a successful strategy.
18 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
19 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
20 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
21 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
22 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
23 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
24 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
25 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
26 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
27 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
28 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
29 Correct 0 ms 204 KB Output is correct
30 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
31 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
32 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
33 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
34 Correct 1 ms 204 KB Output is correct
35 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
36 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
37 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
38 Partially correct 0 ms 284 KB Failed to provide a successful strategy.
39 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
40 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
41 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
42 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
43 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
44 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
45 Correct 0 ms 204 KB Output is correct
46 Correct 1 ms 256 KB Output is correct
47 Correct 0 ms 204 KB Output is correct
48 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
49 Correct 0 ms 204 KB Output is correct
50 Correct 0 ms 204 KB Output is correct
51 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
52 Correct 0 ms 280 KB Output is correct
53 Correct 0 ms 204 KB Output is correct
54 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
55 Correct 0 ms 204 KB Output is correct
56 Correct 0 ms 204 KB Output is correct
57 Correct 0 ms 204 KB Output is correct
58 Correct 0 ms 204 KB Output is correct
59 Correct 1 ms 280 KB Output is correct
60 Correct 0 ms 204 KB Output is correct
61 Correct 0 ms 204 KB Output is correct
62 Correct 0 ms 204 KB Output is correct
63 Correct 0 ms 280 KB Output is correct
64 Correct 0 ms 204 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
5 Partially correct 0 ms 284 KB Failed to provide a successful strategy.
6 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
7 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
8 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
9 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
10 Partially correct 0 ms 212 KB Failed to provide a successful strategy.
11 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
12 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
13 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
14 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
15 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
16 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
17 Partially correct 2 ms 332 KB Failed to provide a successful strategy.
18 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
19 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
20 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
# 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 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
4 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
5 Correct 0 ms 204 KB Output is correct
6 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
7 Correct 0 ms 204 KB Output is correct
8 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
9 Correct 0 ms 204 KB Output is correct
10 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
11 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
12 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
13 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
14 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
15 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
16 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
17 Partially correct 0 ms 276 KB Failed to provide a successful strategy.
18 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
19 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
20 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
21 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
22 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
23 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
24 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
25 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
26 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
27 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
28 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
29 Correct 0 ms 204 KB Output is correct
30 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
31 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
32 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
33 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
34 Correct 1 ms 204 KB Output is correct
35 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
36 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
37 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
38 Partially correct 0 ms 284 KB Failed to provide a successful strategy.
39 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
40 Partially correct 0 ms 280 KB Failed to provide a successful strategy.
41 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
42 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
43 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
44 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
45 Correct 0 ms 204 KB Output is correct
46 Correct 1 ms 256 KB Output is correct
47 Correct 0 ms 204 KB Output is correct
48 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
49 Correct 0 ms 204 KB Output is correct
50 Correct 0 ms 204 KB Output is correct
51 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
52 Correct 0 ms 280 KB Output is correct
53 Correct 0 ms 204 KB Output is correct
54 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
55 Correct 0 ms 204 KB Output is correct
56 Correct 0 ms 204 KB Output is correct
57 Correct 0 ms 204 KB Output is correct
58 Correct 0 ms 204 KB Output is correct
59 Correct 1 ms 280 KB Output is correct
60 Correct 0 ms 204 KB Output is correct
61 Correct 0 ms 204 KB Output is correct
62 Correct 0 ms 204 KB Output is correct
63 Correct 0 ms 280 KB Output is correct
64 Correct 0 ms 204 KB Output is correct
65 Correct 0 ms 204 KB Output is correct
66 Correct 0 ms 204 KB Output is correct
67 Partially correct 0 ms 204 KB Failed to provide a successful strategy.
68 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
69 Correct 1 ms 204 KB Output is correct
70 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
71 Correct 0 ms 204 KB Output is correct
72 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
73 Correct 0 ms 204 KB Output is correct
74 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
75 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
76 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
77 Partially correct 1 ms 204 KB Failed to provide a successful strategy.
78 Partially correct 0 ms 276 KB Failed to provide a successful strategy.
79 Correct 1 ms 332 KB Output is correct
80 Correct 1 ms 332 KB Output is correct
81 Correct 1 ms 332 KB Output is correct
82 Correct 1 ms 332 KB Output is correct
83 Correct 1 ms 332 KB Output is correct
84 Correct 1 ms 332 KB Output is correct
85 Correct 1 ms 332 KB Output is correct
86 Correct 1 ms 332 KB Output is correct
87 Correct 1 ms 332 KB Output is correct
88 Correct 1 ms 332 KB Output is correct
89 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
90 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
91 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
92 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
93 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
94 Partially correct 1 ms 360 KB Failed to provide a successful strategy.
95 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
96 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
97 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
98 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
99 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
100 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
101 Partially correct 1 ms 284 KB Failed to provide a successful strategy.
102 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
103 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
104 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
105 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
106 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
107 Partially correct 1 ms 280 KB Failed to provide a successful strategy.
108 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
109 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
110 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
111 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
112 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
113 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
114 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
115 Partially correct 1 ms 280 KB Failed to provide a successful strategy.
116 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
117 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
118 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
119 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
120 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
121 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
122 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
123 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
124 Partially correct 2 ms 332 KB Failed to provide a successful strategy.
125 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
126 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
127 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
128 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
129 Correct 1 ms 332 KB Output is correct
130 Correct 1 ms 328 KB Output is correct
131 Correct 1 ms 332 KB Output is correct
132 Correct 1 ms 332 KB Output is correct
133 Correct 1 ms 284 KB Output is correct
134 Correct 0 ms 204 KB Output is correct
135 Correct 0 ms 204 KB Output is correct
136 Correct 0 ms 204 KB Output is correct
137 Correct 0 ms 204 KB Output is correct
138 Correct 0 ms 204 KB Output is correct
139 Correct 0 ms 204 KB Output is correct
140 Correct 0 ms 204 KB Output is correct
141 Correct 0 ms 204 KB Output is correct
142 Correct 0 ms 204 KB Output is correct
143 Correct 0 ms 204 KB Output is correct
144 Partially correct 1 ms 332 KB Failed to provide a successful strategy.
145 Partially correct 1 ms 332 KB Failed to provide a successful strategy.