Submission #63206

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
63206	2018-08-01T05:54:53 Z	김세빈(#1833)	Alternating Current (BOI18_alternating)	C++11	33 / 100	3000 ms	18108 KB

alternating

#include <bits/stdc++.h>

using namespace std;

typedef pair <int, int> pii;

vector <int> L[101010], V[101010];
vector <int> X[101010], Y[101010];
set <int> S;
pii P[101010];
int chk[101010], ans[101010];
int fff[101010];
int n, m;

void die() { printf("impossible\n"); exit(0); }

void dfs(int p, int c)
{
	chk[p] = 2; ans[p] = c;
	for(int &t: V[p]){
		if(chk[t] == 1) dfs(t, !c);
		else if(ans[t] == ans[p]) die();
	}
}

int main()
{
	int i, s, e, x, y, a, b;
	
	scanf("%d%d", &n, &m);
	
	for(i=1; i<=m; i++){
		scanf("%d%d", &a, &b);
		b ++; if(b > n) b -= n;
		P[i] = pii(a, b);
		if(a < b){
			L[a].push_back(i);
			L[b].push_back(-i);
		}
		else{
			L[1].push_back(i);
			L[b].push_back(-i);
			L[a].push_back(i);
		}
	}
	
	for(i=1; i<=n; i++){
		for(int &t: L[i]){
			if(t > 0) S.insert(t);
			else S.erase(-t);
		}
		
		if(S.size() == 2){
			a = *S.begin(); b = *next(S.begin());
			V[a].push_back(b);
			V[b].push_back(a);
			chk[a] = 1; chk[b] = 1;
		}
		else if(S.size() == 1) die();
	}
	
	for(i=1; i<=m; i++){
		if(chk[i] == 1) dfs(i, 0);
	}
	
	x = 1;
	
	for(i=1; i<=m; i++){
		if(chk[i]){
			if(ans[i] == 1){
				X[P[i].first].push_back(i);
				x = i;
			}
		}
		else Y[P[i].first].push_back(i);
	}
	
	ans[x] = 1;
	s = P[x].first, e = P[x].second;
	
	for(i=s; ; ){
		for(int &t: X[i]){
			if(P[t].first < P[t].second){
				if(i <= e && e < P[t].second) e = P[t].second;
			}
			else{
				if(i <= e) e = P[t].second;
				else if(e < P[t].second) e = P[t].second;
			}
		}
		for(int &t: Y[i]) y = t;
		
		if(i == e){
			ans[y] = 1;
			e = P[y].second;
		}
		
		i ++; if(i > n) i -= n;
		if(i == s) break;
	}
	
	for(i=1; i<=m; i++){
		if(ans[i] == 0){
			if(P[i].first < P[i].second){
				for(int j=P[i].first; j<P[i].second; j++) fff[j] = 1;
			}
			else{
				for(int j=P[i].first; j<=n; j++) fff[j] = 1;
				for(int j=1; j<P[i].second; j++) fff[j] = 1;
			}
		}
	}
	
	for(i=1; i<=n; i++) if(!fff[i]) die();
	
	for(i=1; i<=m; i++) printf("%d", ans[i]);
	printf("\n");
	
	return 0;
}

Compilation message

alternating.cpp: In function 'int main()':
alternating.cpp:30:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~
alternating.cpp:33:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &a, &b);
   ~~~~~^~~~~~~~~~~~~~~~
alternating.cpp:95:6: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
    e = P[y].second;
    ~~^~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	13 ms	9956 KB	Output is correct
3	Correct	12 ms	10016 KB	Output is correct
4	Correct	11 ms	10064 KB	Output is correct
5	Correct	11 ms	10064 KB	Output is correct
6	Correct	12 ms	10064 KB	Output is correct
7	Correct	10 ms	10064 KB	Output is correct
8	Correct	15 ms	10064 KB	Output is correct
9	Correct	13 ms	10064 KB	Output is correct
10	Correct	15 ms	10168 KB	Output is correct
11	Correct	14 ms	10168 KB	Output is correct
12	Correct	13 ms	10168 KB	Output is correct
13	Correct	13 ms	10168 KB	Output is correct
14	Correct	13 ms	10168 KB	Output is correct
15	Correct	13 ms	10168 KB	Output is correct
16	Correct	12 ms	10168 KB	Output is correct
17	Correct	13 ms	10168 KB	Output is correct
18	Correct	14 ms	10168 KB	Output is correct
19	Correct	11 ms	10168 KB	Output is correct
20	Correct	13 ms	10168 KB	Output is correct
21	Correct	13 ms	10168 KB	Output is correct
22	Correct	11 ms	10168 KB	Output is correct
23	Correct	11 ms	10168 KB	Output is correct
24	Correct	15 ms	10168 KB	Output is correct
25	Correct	11 ms	10168 KB	Output is correct
26	Correct	11 ms	10168 KB	Output is correct
27	Correct	13 ms	10168 KB	Output is correct
28	Correct	14 ms	10168 KB	Output is correct
29	Correct	16 ms	10168 KB	Output is correct
30	Correct	11 ms	10168 KB	Output is correct
31	Correct	13 ms	10168 KB	Output is correct
32	Correct	11 ms	10168 KB	Output is correct
33	Correct	13 ms	10204 KB	Output is correct
34	Correct	15 ms	10204 KB	Output is correct
35	Correct	13 ms	10204 KB	Output is correct
36	Correct	11 ms	10204 KB	Output is correct
37	Correct	13 ms	10204 KB	Output is correct
38	Correct	11 ms	10204 KB	Output is correct
39	Correct	11 ms	10204 KB	Output is correct
40	Correct	13 ms	10204 KB	Output is correct

Subtask #2
20.0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	13 ms	9956 KB	Output is correct
3	Correct	12 ms	10016 KB	Output is correct
4	Correct	11 ms	10064 KB	Output is correct
5	Correct	11 ms	10064 KB	Output is correct
6	Correct	12 ms	10064 KB	Output is correct
7	Correct	10 ms	10064 KB	Output is correct
8	Correct	15 ms	10064 KB	Output is correct
9	Correct	13 ms	10064 KB	Output is correct
10	Correct	15 ms	10168 KB	Output is correct
11	Correct	14 ms	10168 KB	Output is correct
12	Correct	13 ms	10168 KB	Output is correct
13	Correct	13 ms	10168 KB	Output is correct
14	Correct	13 ms	10168 KB	Output is correct
15	Correct	13 ms	10168 KB	Output is correct
16	Correct	12 ms	10168 KB	Output is correct
17	Correct	13 ms	10168 KB	Output is correct
18	Correct	14 ms	10168 KB	Output is correct
19	Correct	11 ms	10168 KB	Output is correct
20	Correct	13 ms	10168 KB	Output is correct
21	Correct	13 ms	10168 KB	Output is correct
22	Correct	11 ms	10168 KB	Output is correct
23	Correct	11 ms	10168 KB	Output is correct
24	Correct	15 ms	10168 KB	Output is correct
25	Correct	11 ms	10168 KB	Output is correct
26	Correct	11 ms	10168 KB	Output is correct
27	Correct	13 ms	10168 KB	Output is correct
28	Correct	14 ms	10168 KB	Output is correct
29	Correct	16 ms	10168 KB	Output is correct
30	Correct	11 ms	10168 KB	Output is correct
31	Correct	13 ms	10168 KB	Output is correct
32	Correct	11 ms	10168 KB	Output is correct
33	Correct	13 ms	10204 KB	Output is correct
34	Correct	15 ms	10204 KB	Output is correct
35	Correct	13 ms	10204 KB	Output is correct
36	Correct	11 ms	10204 KB	Output is correct
37	Correct	13 ms	10204 KB	Output is correct
38	Correct	11 ms	10204 KB	Output is correct
39	Correct	11 ms	10204 KB	Output is correct
40	Correct	13 ms	10204 KB	Output is correct
41	Correct	12 ms	10204 KB	Output is correct
42	Correct	11 ms	10204 KB	Output is correct
43	Correct	14 ms	10204 KB	Output is correct
44	Correct	12 ms	10204 KB	Output is correct
45	Correct	11 ms	10204 KB	Output is correct
46	Correct	12 ms	10204 KB	Output is correct
47	Correct	13 ms	10204 KB	Output is correct
48	Correct	13 ms	10204 KB	Output is correct
49	Correct	12 ms	10204 KB	Output is correct
50	Correct	13 ms	10204 KB	Output is correct
51	Correct	13 ms	10204 KB	Output is correct
52	Correct	12 ms	10204 KB	Output is correct
53	Correct	11 ms	10204 KB	Output is correct
54	Correct	12 ms	10204 KB	Output is correct
55	Correct	13 ms	10204 KB	Output is correct
56	Correct	14 ms	10204 KB	Output is correct
57	Correct	12 ms	10204 KB	Output is correct
58	Correct	14 ms	10204 KB	Output is correct
59	Correct	13 ms	10204 KB	Output is correct
60	Correct	15 ms	10204 KB	Output is correct
61	Correct	15 ms	10204 KB	Output is correct
62	Correct	12 ms	10204 KB	Output is correct
63	Correct	15 ms	10204 KB	Output is correct
64	Correct	14 ms	10228 KB	Output is correct
65	Correct	13 ms	10232 KB	Output is correct
66	Correct	13 ms	10232 KB	Output is correct
67	Correct	13 ms	10232 KB	Output is correct
68	Correct	14 ms	10232 KB	Output is correct
69	Correct	16 ms	10232 KB	Output is correct

Subtask #3
0 / 22.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	13 ms	9956 KB	Output is correct
3	Correct	12 ms	10016 KB	Output is correct
4	Correct	11 ms	10064 KB	Output is correct
5	Correct	11 ms	10064 KB	Output is correct
6	Correct	12 ms	10064 KB	Output is correct
7	Correct	10 ms	10064 KB	Output is correct
8	Correct	15 ms	10064 KB	Output is correct
9	Correct	13 ms	10064 KB	Output is correct
10	Correct	15 ms	10168 KB	Output is correct
11	Correct	14 ms	10168 KB	Output is correct
12	Correct	13 ms	10168 KB	Output is correct
13	Correct	13 ms	10168 KB	Output is correct
14	Correct	13 ms	10168 KB	Output is correct
15	Correct	13 ms	10168 KB	Output is correct
16	Correct	12 ms	10168 KB	Output is correct
17	Correct	13 ms	10168 KB	Output is correct
18	Correct	14 ms	10168 KB	Output is correct
19	Correct	11 ms	10168 KB	Output is correct
20	Correct	13 ms	10168 KB	Output is correct
21	Correct	13 ms	10168 KB	Output is correct
22	Correct	11 ms	10168 KB	Output is correct
23	Correct	11 ms	10168 KB	Output is correct
24	Correct	15 ms	10168 KB	Output is correct
25	Correct	11 ms	10168 KB	Output is correct
26	Correct	11 ms	10168 KB	Output is correct
27	Correct	13 ms	10168 KB	Output is correct
28	Correct	14 ms	10168 KB	Output is correct
29	Correct	16 ms	10168 KB	Output is correct
30	Correct	11 ms	10168 KB	Output is correct
31	Correct	13 ms	10168 KB	Output is correct
32	Correct	11 ms	10168 KB	Output is correct
33	Correct	13 ms	10204 KB	Output is correct
34	Correct	15 ms	10204 KB	Output is correct
35	Correct	13 ms	10204 KB	Output is correct
36	Correct	11 ms	10204 KB	Output is correct
37	Correct	13 ms	10204 KB	Output is correct
38	Correct	11 ms	10204 KB	Output is correct
39	Correct	11 ms	10204 KB	Output is correct
40	Correct	13 ms	10204 KB	Output is correct
41	Correct	12 ms	10204 KB	Output is correct
42	Correct	11 ms	10204 KB	Output is correct
43	Correct	14 ms	10204 KB	Output is correct
44	Correct	12 ms	10204 KB	Output is correct
45	Correct	11 ms	10204 KB	Output is correct
46	Correct	12 ms	10204 KB	Output is correct
47	Correct	13 ms	10204 KB	Output is correct
48	Correct	13 ms	10204 KB	Output is correct
49	Correct	12 ms	10204 KB	Output is correct
50	Correct	13 ms	10204 KB	Output is correct
51	Correct	13 ms	10204 KB	Output is correct
52	Correct	12 ms	10204 KB	Output is correct
53	Correct	11 ms	10204 KB	Output is correct
54	Correct	12 ms	10204 KB	Output is correct
55	Correct	13 ms	10204 KB	Output is correct
56	Correct	14 ms	10204 KB	Output is correct
57	Correct	12 ms	10204 KB	Output is correct
58	Correct	14 ms	10204 KB	Output is correct
59	Correct	13 ms	10204 KB	Output is correct
60	Correct	15 ms	10204 KB	Output is correct
61	Correct	15 ms	10204 KB	Output is correct
62	Correct	12 ms	10204 KB	Output is correct
63	Correct	15 ms	10204 KB	Output is correct
64	Correct	14 ms	10228 KB	Output is correct
65	Correct	13 ms	10232 KB	Output is correct
66	Correct	13 ms	10232 KB	Output is correct
67	Correct	13 ms	10232 KB	Output is correct
68	Correct	14 ms	10232 KB	Output is correct
69	Correct	16 ms	10232 KB	Output is correct
70	Correct	16 ms	10232 KB	Output is correct
71	Correct	15 ms	10284 KB	Output is correct
72	Correct	15 ms	10284 KB	Output is correct
73	Correct	15 ms	10284 KB	Output is correct
74	Correct	13 ms	10284 KB	Output is correct
75	Correct	11 ms	10304 KB	Output is correct
76	Correct	13 ms	10304 KB	Output is correct
77	Correct	11 ms	10304 KB	Output is correct
78	Correct	12 ms	10304 KB	Output is correct
79	Correct	13 ms	10336 KB	Output is correct
80	Correct	14 ms	10336 KB	Output is correct
81	Incorrect	13 ms	10336 KB	no wires in direction 1 between segments 297 and 298
82	Halted	0 ms	0 KB	-

Subtask #4
0 / 19.0

#	Verdict	Execution time	Memory	Grader output
1	Execution timed out	3014 ms	18108 KB	Time limit exceeded
2	Halted	0 ms	0 KB	-

Subtask #5
0 / 26.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	13 ms	9956 KB	Output is correct
3	Correct	12 ms	10016 KB	Output is correct
4	Correct	11 ms	10064 KB	Output is correct
5	Correct	11 ms	10064 KB	Output is correct
6	Correct	12 ms	10064 KB	Output is correct
7	Correct	10 ms	10064 KB	Output is correct
8	Correct	15 ms	10064 KB	Output is correct
9	Correct	13 ms	10064 KB	Output is correct
10	Correct	15 ms	10168 KB	Output is correct
11	Correct	14 ms	10168 KB	Output is correct
12	Correct	13 ms	10168 KB	Output is correct
13	Correct	13 ms	10168 KB	Output is correct
14	Correct	13 ms	10168 KB	Output is correct
15	Correct	13 ms	10168 KB	Output is correct
16	Correct	12 ms	10168 KB	Output is correct
17	Correct	13 ms	10168 KB	Output is correct
18	Correct	14 ms	10168 KB	Output is correct
19	Correct	11 ms	10168 KB	Output is correct
20	Correct	13 ms	10168 KB	Output is correct
21	Correct	13 ms	10168 KB	Output is correct
22	Correct	11 ms	10168 KB	Output is correct
23	Correct	11 ms	10168 KB	Output is correct
24	Correct	15 ms	10168 KB	Output is correct
25	Correct	11 ms	10168 KB	Output is correct
26	Correct	11 ms	10168 KB	Output is correct
27	Correct	13 ms	10168 KB	Output is correct
28	Correct	14 ms	10168 KB	Output is correct
29	Correct	16 ms	10168 KB	Output is correct
30	Correct	11 ms	10168 KB	Output is correct
31	Correct	13 ms	10168 KB	Output is correct
32	Correct	11 ms	10168 KB	Output is correct
33	Correct	13 ms	10204 KB	Output is correct
34	Correct	15 ms	10204 KB	Output is correct
35	Correct	13 ms	10204 KB	Output is correct
36	Correct	11 ms	10204 KB	Output is correct
37	Correct	13 ms	10204 KB	Output is correct
38	Correct	11 ms	10204 KB	Output is correct
39	Correct	11 ms	10204 KB	Output is correct
40	Correct	13 ms	10204 KB	Output is correct
41	Correct	12 ms	10204 KB	Output is correct
42	Correct	11 ms	10204 KB	Output is correct
43	Correct	14 ms	10204 KB	Output is correct
44	Correct	12 ms	10204 KB	Output is correct
45	Correct	11 ms	10204 KB	Output is correct
46	Correct	12 ms	10204 KB	Output is correct
47	Correct	13 ms	10204 KB	Output is correct
48	Correct	13 ms	10204 KB	Output is correct
49	Correct	12 ms	10204 KB	Output is correct
50	Correct	13 ms	10204 KB	Output is correct
51	Correct	13 ms	10204 KB	Output is correct
52	Correct	12 ms	10204 KB	Output is correct
53	Correct	11 ms	10204 KB	Output is correct
54	Correct	12 ms	10204 KB	Output is correct
55	Correct	13 ms	10204 KB	Output is correct
56	Correct	14 ms	10204 KB	Output is correct
57	Correct	12 ms	10204 KB	Output is correct
58	Correct	14 ms	10204 KB	Output is correct
59	Correct	13 ms	10204 KB	Output is correct
60	Correct	15 ms	10204 KB	Output is correct
61	Correct	15 ms	10204 KB	Output is correct
62	Correct	12 ms	10204 KB	Output is correct
63	Correct	15 ms	10204 KB	Output is correct
64	Correct	14 ms	10228 KB	Output is correct
65	Correct	13 ms	10232 KB	Output is correct
66	Correct	13 ms	10232 KB	Output is correct
67	Correct	13 ms	10232 KB	Output is correct
68	Correct	14 ms	10232 KB	Output is correct
69	Correct	16 ms	10232 KB	Output is correct
70	Correct	16 ms	10232 KB	Output is correct
71	Correct	15 ms	10284 KB	Output is correct
72	Correct	15 ms	10284 KB	Output is correct
73	Correct	15 ms	10284 KB	Output is correct
74	Correct	13 ms	10284 KB	Output is correct
75	Correct	11 ms	10304 KB	Output is correct
76	Correct	13 ms	10304 KB	Output is correct
77	Correct	11 ms	10304 KB	Output is correct
78	Correct	12 ms	10304 KB	Output is correct
79	Correct	13 ms	10336 KB	Output is correct
80	Correct	14 ms	10336 KB	Output is correct
81	Incorrect	13 ms	10336 KB	no wires in direction 1 between segments 297 and 298
82	Halted	0 ms	0 KB	-

Submission #63206

Compilation message

Subtask #1 13.0 / 13.0

Subtask #2 20.0 / 20.0

Subtask #3 0 / 22.0

Subtask #4 0 / 19.0

Subtask #5 0 / 26.0

Subtask #1
13.0 / 13.0

Subtask #2
20.0 / 20.0

Subtask #3
0 / 22.0

Subtask #4
0 / 19.0

Subtask #5
0 / 26.0