Submission #63255

# Submission time Handle Problem Language Result Execution time Memory
63255 2018-08-01T07:10:24 Z 김세빈(#1833) Alternating Current (BOI18_alternating) C++11
100 / 100
308 ms 22708 KB
#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 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, j, 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 = i;
		}
	}
	
	ans[x] = 1;
	s = P[x].first;
	
	for(i=1; i<=m; i++){
		P[i].first = (P[i].first - s + n) % n + 1;
		P[i].second = (P[i].second - s + n) % n + 1;
		if(P[i].first >= P[i].second) P[i].second += n;
		
		if(chk[i] && ans[i] == 1) X[P[i].first].push_back(i);
		else if(!chk[i]) Y[P[i].first].push_back(i);
	}
	
	s = 1; e = P[x].second; y = -1;
	
	for(i=1; i<=n; i++){
		for(int &t: X[i]) e = max(e, P[t].second);
		
		if(i == e){
			y = -1;
			for(j=s; j<=e; j++){
				for(int &t: Y[j]){
					if(P[t].second > e){
						if(y == -1) y = t;
						else if(P[t].second > P[y].second) y = t;
					}
				}
			}
			if(y == -1) die();
			
			ans[y] = 1;
			e = P[y].second;
			s = i = P[y].first;
			y = -1;
		}
	}
	
	for(i=1; i<=m; i++) printf("%d", ans[i]);
	printf("\n");
	
	return 0;
}

Compilation message

alternating.cpp: In function 'int main()':
alternating.cpp:29:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~
alternating.cpp:32:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &a, &b);
   ~~~~~^~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 10 ms 9720 KB Output is correct
2 Correct 10 ms 9828 KB Output is correct
3 Correct 10 ms 9880 KB Output is correct
4 Correct 12 ms 9880 KB Output is correct
5 Correct 11 ms 9880 KB Output is correct
6 Correct 11 ms 9940 KB Output is correct
7 Correct 10 ms 10040 KB Output is correct
8 Correct 13 ms 10040 KB Output is correct
9 Correct 10 ms 10040 KB Output is correct
10 Correct 13 ms 10040 KB Output is correct
11 Correct 11 ms 10040 KB Output is correct
12 Correct 11 ms 10040 KB Output is correct
13 Correct 11 ms 10064 KB Output is correct
14 Correct 11 ms 10064 KB Output is correct
15 Correct 11 ms 10172 KB Output is correct
16 Correct 11 ms 10172 KB Output is correct
17 Correct 10 ms 10172 KB Output is correct
18 Correct 13 ms 10172 KB Output is correct
19 Correct 10 ms 10172 KB Output is correct
20 Correct 11 ms 10172 KB Output is correct
21 Correct 12 ms 10172 KB Output is correct
22 Correct 15 ms 10172 KB Output is correct
23 Correct 14 ms 10172 KB Output is correct
24 Correct 15 ms 10172 KB Output is correct
25 Correct 13 ms 10172 KB Output is correct
26 Correct 11 ms 10172 KB Output is correct
27 Correct 13 ms 10172 KB Output is correct
28 Correct 11 ms 10172 KB Output is correct
29 Correct 13 ms 10172 KB Output is correct
30 Correct 13 ms 10204 KB Output is correct
31 Correct 13 ms 10204 KB Output is correct
32 Correct 12 ms 10204 KB Output is correct
33 Correct 11 ms 10204 KB Output is correct
34 Correct 10 ms 10204 KB Output is correct
35 Correct 14 ms 10204 KB Output is correct
36 Correct 15 ms 10204 KB Output is correct
37 Correct 10 ms 10204 KB Output is correct
38 Correct 13 ms 10204 KB Output is correct
39 Correct 13 ms 10204 KB Output is correct
40 Correct 11 ms 10204 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 10 ms 9720 KB Output is correct
2 Correct 10 ms 9828 KB Output is correct
3 Correct 10 ms 9880 KB Output is correct
4 Correct 12 ms 9880 KB Output is correct
5 Correct 11 ms 9880 KB Output is correct
6 Correct 11 ms 9940 KB Output is correct
7 Correct 10 ms 10040 KB Output is correct
8 Correct 13 ms 10040 KB Output is correct
9 Correct 10 ms 10040 KB Output is correct
10 Correct 13 ms 10040 KB Output is correct
11 Correct 11 ms 10040 KB Output is correct
12 Correct 11 ms 10040 KB Output is correct
13 Correct 11 ms 10064 KB Output is correct
14 Correct 11 ms 10064 KB Output is correct
15 Correct 11 ms 10172 KB Output is correct
16 Correct 11 ms 10172 KB Output is correct
17 Correct 10 ms 10172 KB Output is correct
18 Correct 13 ms 10172 KB Output is correct
19 Correct 10 ms 10172 KB Output is correct
20 Correct 11 ms 10172 KB Output is correct
21 Correct 12 ms 10172 KB Output is correct
22 Correct 15 ms 10172 KB Output is correct
23 Correct 14 ms 10172 KB Output is correct
24 Correct 15 ms 10172 KB Output is correct
25 Correct 13 ms 10172 KB Output is correct
26 Correct 11 ms 10172 KB Output is correct
27 Correct 13 ms 10172 KB Output is correct
28 Correct 11 ms 10172 KB Output is correct
29 Correct 13 ms 10172 KB Output is correct
30 Correct 13 ms 10204 KB Output is correct
31 Correct 13 ms 10204 KB Output is correct
32 Correct 12 ms 10204 KB Output is correct
33 Correct 11 ms 10204 KB Output is correct
34 Correct 10 ms 10204 KB Output is correct
35 Correct 14 ms 10204 KB Output is correct
36 Correct 15 ms 10204 KB Output is correct
37 Correct 10 ms 10204 KB Output is correct
38 Correct 13 ms 10204 KB Output is correct
39 Correct 13 ms 10204 KB Output is correct
40 Correct 11 ms 10204 KB Output is correct
41 Correct 12 ms 10204 KB Output is correct
42 Correct 10 ms 10204 KB Output is correct
43 Correct 10 ms 10204 KB Output is correct
44 Correct 10 ms 10204 KB Output is correct
45 Correct 11 ms 10204 KB Output is correct
46 Correct 11 ms 10204 KB Output is correct
47 Correct 11 ms 10204 KB Output is correct
48 Correct 11 ms 10204 KB Output is correct
49 Correct 11 ms 10204 KB Output is correct
50 Correct 14 ms 10204 KB Output is correct
51 Correct 12 ms 10204 KB Output is correct
52 Correct 11 ms 10204 KB Output is correct
53 Correct 10 ms 10204 KB Output is correct
54 Correct 10 ms 10204 KB Output is correct
55 Correct 13 ms 10204 KB Output is correct
56 Correct 15 ms 10204 KB Output is correct
57 Correct 10 ms 10204 KB Output is correct
58 Correct 12 ms 10204 KB Output is correct
59 Correct 14 ms 10204 KB Output is correct
60 Correct 12 ms 10204 KB Output is correct
61 Correct 12 ms 10204 KB Output is correct
62 Correct 13 ms 10204 KB Output is correct
63 Correct 12 ms 10204 KB Output is correct
64 Correct 15 ms 10204 KB Output is correct
65 Correct 13 ms 10204 KB Output is correct
66 Correct 13 ms 10204 KB Output is correct
67 Correct 13 ms 10204 KB Output is correct
68 Correct 11 ms 10204 KB Output is correct
69 Correct 11 ms 10212 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 10 ms 9720 KB Output is correct
2 Correct 10 ms 9828 KB Output is correct
3 Correct 10 ms 9880 KB Output is correct
4 Correct 12 ms 9880 KB Output is correct
5 Correct 11 ms 9880 KB Output is correct
6 Correct 11 ms 9940 KB Output is correct
7 Correct 10 ms 10040 KB Output is correct
8 Correct 13 ms 10040 KB Output is correct
9 Correct 10 ms 10040 KB Output is correct
10 Correct 13 ms 10040 KB Output is correct
11 Correct 11 ms 10040 KB Output is correct
12 Correct 11 ms 10040 KB Output is correct
13 Correct 11 ms 10064 KB Output is correct
14 Correct 11 ms 10064 KB Output is correct
15 Correct 11 ms 10172 KB Output is correct
16 Correct 11 ms 10172 KB Output is correct
17 Correct 10 ms 10172 KB Output is correct
18 Correct 13 ms 10172 KB Output is correct
19 Correct 10 ms 10172 KB Output is correct
20 Correct 11 ms 10172 KB Output is correct
21 Correct 12 ms 10172 KB Output is correct
22 Correct 15 ms 10172 KB Output is correct
23 Correct 14 ms 10172 KB Output is correct
24 Correct 15 ms 10172 KB Output is correct
25 Correct 13 ms 10172 KB Output is correct
26 Correct 11 ms 10172 KB Output is correct
27 Correct 13 ms 10172 KB Output is correct
28 Correct 11 ms 10172 KB Output is correct
29 Correct 13 ms 10172 KB Output is correct
30 Correct 13 ms 10204 KB Output is correct
31 Correct 13 ms 10204 KB Output is correct
32 Correct 12 ms 10204 KB Output is correct
33 Correct 11 ms 10204 KB Output is correct
34 Correct 10 ms 10204 KB Output is correct
35 Correct 14 ms 10204 KB Output is correct
36 Correct 15 ms 10204 KB Output is correct
37 Correct 10 ms 10204 KB Output is correct
38 Correct 13 ms 10204 KB Output is correct
39 Correct 13 ms 10204 KB Output is correct
40 Correct 11 ms 10204 KB Output is correct
41 Correct 12 ms 10204 KB Output is correct
42 Correct 10 ms 10204 KB Output is correct
43 Correct 10 ms 10204 KB Output is correct
44 Correct 10 ms 10204 KB Output is correct
45 Correct 11 ms 10204 KB Output is correct
46 Correct 11 ms 10204 KB Output is correct
47 Correct 11 ms 10204 KB Output is correct
48 Correct 11 ms 10204 KB Output is correct
49 Correct 11 ms 10204 KB Output is correct
50 Correct 14 ms 10204 KB Output is correct
51 Correct 12 ms 10204 KB Output is correct
52 Correct 11 ms 10204 KB Output is correct
53 Correct 10 ms 10204 KB Output is correct
54 Correct 10 ms 10204 KB Output is correct
55 Correct 13 ms 10204 KB Output is correct
56 Correct 15 ms 10204 KB Output is correct
57 Correct 10 ms 10204 KB Output is correct
58 Correct 12 ms 10204 KB Output is correct
59 Correct 14 ms 10204 KB Output is correct
60 Correct 12 ms 10204 KB Output is correct
61 Correct 12 ms 10204 KB Output is correct
62 Correct 13 ms 10204 KB Output is correct
63 Correct 12 ms 10204 KB Output is correct
64 Correct 15 ms 10204 KB Output is correct
65 Correct 13 ms 10204 KB Output is correct
66 Correct 13 ms 10204 KB Output is correct
67 Correct 13 ms 10204 KB Output is correct
68 Correct 11 ms 10204 KB Output is correct
69 Correct 11 ms 10212 KB Output is correct
70 Correct 11 ms 10212 KB Output is correct
71 Correct 12 ms 10236 KB Output is correct
72 Correct 10 ms 10236 KB Output is correct
73 Correct 9 ms 10236 KB Output is correct
74 Correct 11 ms 10236 KB Output is correct
75 Correct 10 ms 10236 KB Output is correct
76 Correct 13 ms 10236 KB Output is correct
77 Correct 10 ms 10236 KB Output is correct
78 Correct 10 ms 10236 KB Output is correct
79 Correct 10 ms 10236 KB Output is correct
80 Correct 11 ms 10236 KB Output is correct
81 Correct 10 ms 10236 KB Output is correct
82 Correct 10 ms 10236 KB Output is correct
83 Correct 14 ms 10236 KB Output is correct
84 Correct 11 ms 10236 KB Output is correct
85 Correct 13 ms 10236 KB Output is correct
86 Correct 14 ms 10236 KB Output is correct
87 Correct 12 ms 10236 KB Output is correct
88 Correct 11 ms 10236 KB Output is correct
89 Correct 14 ms 10236 KB Output is correct
90 Correct 12 ms 10236 KB Output is correct
91 Correct 13 ms 10236 KB Output is correct
92 Correct 12 ms 10236 KB Output is correct
93 Correct 11 ms 10236 KB Output is correct
94 Correct 12 ms 10236 KB Output is correct
95 Correct 14 ms 10236 KB Output is correct
96 Correct 12 ms 10236 KB Output is correct
97 Correct 10 ms 10236 KB Output is correct
98 Correct 15 ms 10236 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 114 ms 17812 KB Output is correct
2 Correct 14 ms 17812 KB Output is correct
3 Correct 34 ms 17812 KB Output is correct
4 Correct 68 ms 17812 KB Output is correct
5 Correct 146 ms 18444 KB Output is correct
6 Correct 135 ms 18444 KB Output is correct
7 Correct 139 ms 18444 KB Output is correct
8 Correct 19 ms 18444 KB Output is correct
9 Correct 19 ms 18444 KB Output is correct
10 Correct 172 ms 18716 KB Output is correct
11 Correct 123 ms 18716 KB Output is correct
12 Correct 129 ms 18716 KB Output is correct
13 Correct 14 ms 18716 KB Output is correct
14 Correct 19 ms 18716 KB Output is correct
15 Correct 191 ms 18716 KB Output is correct
16 Correct 64 ms 18716 KB Output is correct
17 Correct 308 ms 18716 KB Output is correct
18 Correct 151 ms 18716 KB Output is correct
19 Correct 21 ms 18716 KB Output is correct
20 Correct 94 ms 18716 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 10 ms 9720 KB Output is correct
2 Correct 10 ms 9828 KB Output is correct
3 Correct 10 ms 9880 KB Output is correct
4 Correct 12 ms 9880 KB Output is correct
5 Correct 11 ms 9880 KB Output is correct
6 Correct 11 ms 9940 KB Output is correct
7 Correct 10 ms 10040 KB Output is correct
8 Correct 13 ms 10040 KB Output is correct
9 Correct 10 ms 10040 KB Output is correct
10 Correct 13 ms 10040 KB Output is correct
11 Correct 11 ms 10040 KB Output is correct
12 Correct 11 ms 10040 KB Output is correct
13 Correct 11 ms 10064 KB Output is correct
14 Correct 11 ms 10064 KB Output is correct
15 Correct 11 ms 10172 KB Output is correct
16 Correct 11 ms 10172 KB Output is correct
17 Correct 10 ms 10172 KB Output is correct
18 Correct 13 ms 10172 KB Output is correct
19 Correct 10 ms 10172 KB Output is correct
20 Correct 11 ms 10172 KB Output is correct
21 Correct 12 ms 10172 KB Output is correct
22 Correct 15 ms 10172 KB Output is correct
23 Correct 14 ms 10172 KB Output is correct
24 Correct 15 ms 10172 KB Output is correct
25 Correct 13 ms 10172 KB Output is correct
26 Correct 11 ms 10172 KB Output is correct
27 Correct 13 ms 10172 KB Output is correct
28 Correct 11 ms 10172 KB Output is correct
29 Correct 13 ms 10172 KB Output is correct
30 Correct 13 ms 10204 KB Output is correct
31 Correct 13 ms 10204 KB Output is correct
32 Correct 12 ms 10204 KB Output is correct
33 Correct 11 ms 10204 KB Output is correct
34 Correct 10 ms 10204 KB Output is correct
35 Correct 14 ms 10204 KB Output is correct
36 Correct 15 ms 10204 KB Output is correct
37 Correct 10 ms 10204 KB Output is correct
38 Correct 13 ms 10204 KB Output is correct
39 Correct 13 ms 10204 KB Output is correct
40 Correct 11 ms 10204 KB Output is correct
41 Correct 12 ms 10204 KB Output is correct
42 Correct 10 ms 10204 KB Output is correct
43 Correct 10 ms 10204 KB Output is correct
44 Correct 10 ms 10204 KB Output is correct
45 Correct 11 ms 10204 KB Output is correct
46 Correct 11 ms 10204 KB Output is correct
47 Correct 11 ms 10204 KB Output is correct
48 Correct 11 ms 10204 KB Output is correct
49 Correct 11 ms 10204 KB Output is correct
50 Correct 14 ms 10204 KB Output is correct
51 Correct 12 ms 10204 KB Output is correct
52 Correct 11 ms 10204 KB Output is correct
53 Correct 10 ms 10204 KB Output is correct
54 Correct 10 ms 10204 KB Output is correct
55 Correct 13 ms 10204 KB Output is correct
56 Correct 15 ms 10204 KB Output is correct
57 Correct 10 ms 10204 KB Output is correct
58 Correct 12 ms 10204 KB Output is correct
59 Correct 14 ms 10204 KB Output is correct
60 Correct 12 ms 10204 KB Output is correct
61 Correct 12 ms 10204 KB Output is correct
62 Correct 13 ms 10204 KB Output is correct
63 Correct 12 ms 10204 KB Output is correct
64 Correct 15 ms 10204 KB Output is correct
65 Correct 13 ms 10204 KB Output is correct
66 Correct 13 ms 10204 KB Output is correct
67 Correct 13 ms 10204 KB Output is correct
68 Correct 11 ms 10204 KB Output is correct
69 Correct 11 ms 10212 KB Output is correct
70 Correct 11 ms 10212 KB Output is correct
71 Correct 12 ms 10236 KB Output is correct
72 Correct 10 ms 10236 KB Output is correct
73 Correct 9 ms 10236 KB Output is correct
74 Correct 11 ms 10236 KB Output is correct
75 Correct 10 ms 10236 KB Output is correct
76 Correct 13 ms 10236 KB Output is correct
77 Correct 10 ms 10236 KB Output is correct
78 Correct 10 ms 10236 KB Output is correct
79 Correct 10 ms 10236 KB Output is correct
80 Correct 11 ms 10236 KB Output is correct
81 Correct 10 ms 10236 KB Output is correct
82 Correct 10 ms 10236 KB Output is correct
83 Correct 14 ms 10236 KB Output is correct
84 Correct 11 ms 10236 KB Output is correct
85 Correct 13 ms 10236 KB Output is correct
86 Correct 14 ms 10236 KB Output is correct
87 Correct 12 ms 10236 KB Output is correct
88 Correct 11 ms 10236 KB Output is correct
89 Correct 14 ms 10236 KB Output is correct
90 Correct 12 ms 10236 KB Output is correct
91 Correct 13 ms 10236 KB Output is correct
92 Correct 12 ms 10236 KB Output is correct
93 Correct 11 ms 10236 KB Output is correct
94 Correct 12 ms 10236 KB Output is correct
95 Correct 14 ms 10236 KB Output is correct
96 Correct 12 ms 10236 KB Output is correct
97 Correct 10 ms 10236 KB Output is correct
98 Correct 15 ms 10236 KB Output is correct
99 Correct 114 ms 17812 KB Output is correct
100 Correct 14 ms 17812 KB Output is correct
101 Correct 34 ms 17812 KB Output is correct
102 Correct 68 ms 17812 KB Output is correct
103 Correct 146 ms 18444 KB Output is correct
104 Correct 135 ms 18444 KB Output is correct
105 Correct 139 ms 18444 KB Output is correct
106 Correct 19 ms 18444 KB Output is correct
107 Correct 19 ms 18444 KB Output is correct
108 Correct 172 ms 18716 KB Output is correct
109 Correct 123 ms 18716 KB Output is correct
110 Correct 129 ms 18716 KB Output is correct
111 Correct 14 ms 18716 KB Output is correct
112 Correct 19 ms 18716 KB Output is correct
113 Correct 191 ms 18716 KB Output is correct
114 Correct 64 ms 18716 KB Output is correct
115 Correct 308 ms 18716 KB Output is correct
116 Correct 151 ms 18716 KB Output is correct
117 Correct 21 ms 18716 KB Output is correct
118 Correct 94 ms 18716 KB Output is correct
119 Correct 14 ms 18716 KB Output is correct
120 Correct 159 ms 19888 KB Output is correct
121 Correct 95 ms 19888 KB Output is correct
122 Correct 15 ms 19888 KB Output is correct
123 Correct 19 ms 19888 KB Output is correct
124 Correct 46 ms 19888 KB Output is correct
125 Correct 79 ms 19888 KB Output is correct
126 Correct 14 ms 19888 KB Output is correct
127 Correct 32 ms 19888 KB Output is correct
128 Correct 128 ms 19888 KB Output is correct
129 Correct 75 ms 19888 KB Output is correct
130 Correct 142 ms 19888 KB Output is correct
131 Correct 16 ms 19888 KB Output is correct
132 Correct 15 ms 19888 KB Output is correct
133 Correct 235 ms 22708 KB Output is correct
134 Correct 67 ms 22708 KB Output is correct
135 Correct 11 ms 22708 KB Output is correct
136 Correct 49 ms 22708 KB Output is correct
137 Correct 102 ms 22708 KB Output is correct
138 Correct 18 ms 22708 KB Output is correct