Submission #63215

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
63215	2018-08-01T06:08:50 Z	김세빈(#1833)	Alternating Current (BOI18_alternating)	C++11	0 / 100	3000 ms	18636 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; y = -1;
	s = P[x].first, e = P[x].second;
	
	if(s != e){
		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]){
				if(y == -1) y = t;
				else if(P[t].first < P[t].second){
					if(i <= P[y].second && P[y].second < P[t].second) y = t;
				}
				else{
					if(i <= P[y].second) y = t;
					else if(P[y].second < P[t].second) y = t;
				}
			}
			
			if(i == e){
				if(y == -1) die();
				ans[y] = 1;
				if(P[y].first == P[y].second) break;
				e = P[y].second;
				i = P[y].first;
				y = -1;
			}
			else{
				i ++; if(i > n) i -= n;
				if(i == s) break;
			}
		}
	}
	
	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);
   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	14 ms	9828 KB	Output is correct
3	Correct	13 ms	9904 KB	Output is correct
4	Correct	14 ms	9920 KB	Output is correct
5	Correct	12 ms	9976 KB	Output is correct
6	Correct	13 ms	10080 KB	Output is correct
7	Correct	14 ms	10084 KB	Output is correct
8	Correct	12 ms	10084 KB	Output is correct
9	Correct	11 ms	10084 KB	Output is correct
10	Correct	11 ms	10084 KB	Output is correct
11	Correct	11 ms	10084 KB	Output is correct
12	Correct	13 ms	10084 KB	Output is correct
13	Correct	14 ms	10084 KB	Output is correct
14	Correct	12 ms	10084 KB	Output is correct
15	Correct	11 ms	10084 KB	Output is correct
16	Correct	12 ms	10084 KB	Output is correct
17	Correct	14 ms	10084 KB	Output is correct
18	Correct	14 ms	10136 KB	Output is correct
19	Correct	14 ms	10136 KB	Output is correct
20	Correct	13 ms	10204 KB	Output is correct
21	Correct	7 ms	10204 KB	Output is correct
22	Correct	13 ms	10204 KB	Output is correct
23	Correct	13 ms	10204 KB	Output is correct
24	Correct	12 ms	10204 KB	Output is correct
25	Correct	12 ms	10204 KB	Output is correct
26	Correct	12 ms	10204 KB	Output is correct
27	Correct	14 ms	10204 KB	Output is correct
28	Correct	12 ms	10204 KB	Output is correct
29	Correct	14 ms	10204 KB	Output is correct
30	Correct	11 ms	10204 KB	Output is correct
31	Correct	13 ms	10204 KB	Output is correct
32	Correct	13 ms	10204 KB	Output is correct
33	Correct	15 ms	10204 KB	Output is correct
34	Correct	12 ms	10204 KB	Output is correct
35	Correct	14 ms	10204 KB	Output is correct
36	Execution timed out	3030 ms	10208 KB	Time limit exceeded
37	Halted	0 ms	0 KB	-

Subtask #2
0 / 20.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	14 ms	9828 KB	Output is correct
3	Correct	13 ms	9904 KB	Output is correct
4	Correct	14 ms	9920 KB	Output is correct
5	Correct	12 ms	9976 KB	Output is correct
6	Correct	13 ms	10080 KB	Output is correct
7	Correct	14 ms	10084 KB	Output is correct
8	Correct	12 ms	10084 KB	Output is correct
9	Correct	11 ms	10084 KB	Output is correct
10	Correct	11 ms	10084 KB	Output is correct
11	Correct	11 ms	10084 KB	Output is correct
12	Correct	13 ms	10084 KB	Output is correct
13	Correct	14 ms	10084 KB	Output is correct
14	Correct	12 ms	10084 KB	Output is correct
15	Correct	11 ms	10084 KB	Output is correct
16	Correct	12 ms	10084 KB	Output is correct
17	Correct	14 ms	10084 KB	Output is correct
18	Correct	14 ms	10136 KB	Output is correct
19	Correct	14 ms	10136 KB	Output is correct
20	Correct	13 ms	10204 KB	Output is correct
21	Correct	7 ms	10204 KB	Output is correct
22	Correct	13 ms	10204 KB	Output is correct
23	Correct	13 ms	10204 KB	Output is correct
24	Correct	12 ms	10204 KB	Output is correct
25	Correct	12 ms	10204 KB	Output is correct
26	Correct	12 ms	10204 KB	Output is correct
27	Correct	14 ms	10204 KB	Output is correct
28	Correct	12 ms	10204 KB	Output is correct
29	Correct	14 ms	10204 KB	Output is correct
30	Correct	11 ms	10204 KB	Output is correct
31	Correct	13 ms	10204 KB	Output is correct
32	Correct	13 ms	10204 KB	Output is correct
33	Correct	15 ms	10204 KB	Output is correct
34	Correct	12 ms	10204 KB	Output is correct
35	Correct	14 ms	10204 KB	Output is correct
36	Execution timed out	3030 ms	10208 KB	Time limit exceeded
37	Halted	0 ms	0 KB	-

Subtask #3
0 / 22.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	9720 KB	Output is correct
2	Correct	14 ms	9828 KB	Output is correct
3	Correct	13 ms	9904 KB	Output is correct
4	Correct	14 ms	9920 KB	Output is correct
5	Correct	12 ms	9976 KB	Output is correct
6	Correct	13 ms	10080 KB	Output is correct
7	Correct	14 ms	10084 KB	Output is correct
8	Correct	12 ms	10084 KB	Output is correct
9	Correct	11 ms	10084 KB	Output is correct
10	Correct	11 ms	10084 KB	Output is correct
11	Correct	11 ms	10084 KB	Output is correct
12	Correct	13 ms	10084 KB	Output is correct
13	Correct	14 ms	10084 KB	Output is correct
14	Correct	12 ms	10084 KB	Output is correct
15	Correct	11 ms	10084 KB	Output is correct
16	Correct	12 ms	10084 KB	Output is correct
17	Correct	14 ms	10084 KB	Output is correct
18	Correct	14 ms	10136 KB	Output is correct
19	Correct	14 ms	10136 KB	Output is correct
20	Correct	13 ms	10204 KB	Output is correct
21	Correct	7 ms	10204 KB	Output is correct
22	Correct	13 ms	10204 KB	Output is correct
23	Correct	13 ms	10204 KB	Output is correct
24	Correct	12 ms	10204 KB	Output is correct
25	Correct	12 ms	10204 KB	Output is correct
26	Correct	12 ms	10204 KB	Output is correct
27	Correct	14 ms	10204 KB	Output is correct
28	Correct	12 ms	10204 KB	Output is correct
29	Correct	14 ms	10204 KB	Output is correct
30	Correct	11 ms	10204 KB	Output is correct
31	Correct	13 ms	10204 KB	Output is correct
32	Correct	13 ms	10204 KB	Output is correct
33	Correct	15 ms	10204 KB	Output is correct
34	Correct	12 ms	10204 KB	Output is correct
35	Correct	14 ms	10204 KB	Output is correct
36	Execution timed out	3030 ms	10208 KB	Time limit exceeded
37	Halted	0 ms	0 KB	-

Subtask #4
0 / 19.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	152 ms	17784 KB	Output is correct
2	Correct	15 ms	17784 KB	Output is correct
3	Correct	47 ms	17784 KB	Output is correct
4	Correct	93 ms	17784 KB	Output is correct
5	Correct	242 ms	18636 KB	Output is correct
6	Correct	146 ms	18636 KB	Output is correct
7	Execution timed out	3055 ms	18636 KB	Time limit exceeded
8	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	14 ms	9828 KB	Output is correct
3	Correct	13 ms	9904 KB	Output is correct
4	Correct	14 ms	9920 KB	Output is correct
5	Correct	12 ms	9976 KB	Output is correct
6	Correct	13 ms	10080 KB	Output is correct
7	Correct	14 ms	10084 KB	Output is correct
8	Correct	12 ms	10084 KB	Output is correct
9	Correct	11 ms	10084 KB	Output is correct
10	Correct	11 ms	10084 KB	Output is correct
11	Correct	11 ms	10084 KB	Output is correct
12	Correct	13 ms	10084 KB	Output is correct
13	Correct	14 ms	10084 KB	Output is correct
14	Correct	12 ms	10084 KB	Output is correct
15	Correct	11 ms	10084 KB	Output is correct
16	Correct	12 ms	10084 KB	Output is correct
17	Correct	14 ms	10084 KB	Output is correct
18	Correct	14 ms	10136 KB	Output is correct
19	Correct	14 ms	10136 KB	Output is correct
20	Correct	13 ms	10204 KB	Output is correct
21	Correct	7 ms	10204 KB	Output is correct
22	Correct	13 ms	10204 KB	Output is correct
23	Correct	13 ms	10204 KB	Output is correct
24	Correct	12 ms	10204 KB	Output is correct
25	Correct	12 ms	10204 KB	Output is correct
26	Correct	12 ms	10204 KB	Output is correct
27	Correct	14 ms	10204 KB	Output is correct
28	Correct	12 ms	10204 KB	Output is correct
29	Correct	14 ms	10204 KB	Output is correct
30	Correct	11 ms	10204 KB	Output is correct
31	Correct	13 ms	10204 KB	Output is correct
32	Correct	13 ms	10204 KB	Output is correct
33	Correct	15 ms	10204 KB	Output is correct
34	Correct	12 ms	10204 KB	Output is correct
35	Correct	14 ms	10204 KB	Output is correct
36	Execution timed out	3030 ms	10208 KB	Time limit exceeded
37	Halted	0 ms	0 KB	-

Submission #63215

Compilation message

Subtask #1 0 / 13.0

Subtask #2 0 / 20.0

Subtask #3 0 / 22.0

Subtask #4 0 / 19.0

Subtask #5 0 / 26.0

Subtask #1
0 / 13.0

Subtask #2
0 / 20.0

Subtask #3
0 / 22.0

Subtask #4
0 / 19.0

Subtask #5
0 / 26.0