#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define all(aaa) aaa.begin(), aaa.end()
struct Seg {
int l, r, i;
};
const int N = 2e5 + 5;
vector<Seg> v;
int dp[N], w[N], nt[N];
string ans;
signed main() {
#ifdef HOME
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(0);
int n, m;
cin >> n >> m;
for (int i = 0; i < m; i++) {
int a, b;
cin >> a >> b;
v.push_back({ a - 1, b - 1, i });
}
int x = -1, mx_len = 0;
for (int i = 0; i < n; i++) {
int len;
if (v[i].l <= v[i].r)
len = v[i].r - v[i].l + 1;
else
len = m - v[i].l + 1 + v[i].r;
if (len > mx_len) {
mx_len = len;
x = i;
}
}
int b = v[x].l, id = v[x].i;
for (int i = 0; i < m; i++) {
v[i].l = (v[i].l - b + n) % n;
v[i].r = (v[i].r - b + n) % n;
w[v[i].l]++;
w[v[i].r + 1]--;
if (v[i].l > v[i].r) {
w[0]++;
v[i].r += n;
}
}
for (int i = 0; i < n; i++) {
w[i + 1] += w[i];
if (w[i] < 2) {
cout << "impossible";
return 0;
}
}
for (int i = n - 1, j = n; i >= 0; i--) {
if (w[i] < 3)
j = i;
nt[i] = j;
}
// for (int i = 0; i < n; i++) {
// cout << w[i];
// }
// cout << "\n";
sort(all(v), [](Seg a, Seg b) {
return a.r < b.r;
});
x = 0;
while (v[x].i != id)
x++;
fill(dp, dp + m, -1);
dp[x] = -2;
set<pair<int, int>> st = { { v[x].r, x } };
for (int i = x + 1; i < m; i++) {
auto it = st.lower_bound({ v[i].l - 1, -1 });
if (it != st.end() && it->first == v[i].l - 1) {
dp[i] = it->second;
}
else {
it = st.lower_bound({ v[i].l, -1 });
if (it != st.end() && it->first < nt[v[i].l]) {
dp[i] = it->second;
}
}
if (dp[i] != -1) {
st.insert({ v[i].r, i });
}
}
int y = -1;
for (int i = 0; i < m; i++) {
if (dp[i] != -1 && (v[i].r == n - 1 || v[i].r >= n && v[i].r % n < nt[0])) {
y = i;
break;
}
}
if (y == -1) {
cout << "impossible";
return 0;
}
vector<Seg> part;
while (y >= 0) {
part.push_back(v[y]);
y = dp[y];
}
reverse(all(part));
if (part.size() > 2 && part.back().r >= n &&
part.back().r % n >= part[1].l - 1) {
part.erase(part.begin());
}
ans.resize(m, '0');
for (Seg s : part) {
ans[s.i] = '1';
}
cout << ans;
return 0;
}
Compilation message
alternating.cpp: In function 'int main()':
alternating.cpp:117:64: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
if (dp[i] != -1 && (v[i].r == n - 1 || v[i].r >= n && v[i].r % n < nt[0])) {
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
380 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
420 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
376 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
380 KB |
Output is correct |
18 |
Correct |
2 ms |
348 KB |
Output is correct |
19 |
Correct |
2 ms |
376 KB |
Output is correct |
20 |
Correct |
2 ms |
376 KB |
Output is correct |
21 |
Correct |
2 ms |
376 KB |
Output is correct |
22 |
Correct |
2 ms |
424 KB |
Output is correct |
23 |
Correct |
2 ms |
384 KB |
Output is correct |
24 |
Correct |
2 ms |
380 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
376 KB |
Output is correct |
30 |
Correct |
2 ms |
376 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
376 KB |
Output is correct |
34 |
Correct |
2 ms |
376 KB |
Output is correct |
35 |
Correct |
2 ms |
376 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
376 KB |
Output is correct |
38 |
Correct |
2 ms |
376 KB |
Output is correct |
39 |
Correct |
2 ms |
376 KB |
Output is correct |
40 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
380 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
420 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
376 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
380 KB |
Output is correct |
18 |
Correct |
2 ms |
348 KB |
Output is correct |
19 |
Correct |
2 ms |
376 KB |
Output is correct |
20 |
Correct |
2 ms |
376 KB |
Output is correct |
21 |
Correct |
2 ms |
376 KB |
Output is correct |
22 |
Correct |
2 ms |
424 KB |
Output is correct |
23 |
Correct |
2 ms |
384 KB |
Output is correct |
24 |
Correct |
2 ms |
380 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
376 KB |
Output is correct |
30 |
Correct |
2 ms |
376 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
376 KB |
Output is correct |
34 |
Correct |
2 ms |
376 KB |
Output is correct |
35 |
Correct |
2 ms |
376 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
376 KB |
Output is correct |
38 |
Correct |
2 ms |
376 KB |
Output is correct |
39 |
Correct |
2 ms |
376 KB |
Output is correct |
40 |
Correct |
2 ms |
376 KB |
Output is correct |
41 |
Correct |
2 ms |
376 KB |
Output is correct |
42 |
Correct |
2 ms |
376 KB |
Output is correct |
43 |
Correct |
2 ms |
376 KB |
Output is correct |
44 |
Correct |
2 ms |
376 KB |
Output is correct |
45 |
Correct |
2 ms |
376 KB |
Output is correct |
46 |
Correct |
2 ms |
376 KB |
Output is correct |
47 |
Correct |
2 ms |
376 KB |
Output is correct |
48 |
Correct |
2 ms |
376 KB |
Output is correct |
49 |
Correct |
2 ms |
376 KB |
Output is correct |
50 |
Correct |
2 ms |
376 KB |
Output is correct |
51 |
Correct |
2 ms |
388 KB |
Output is correct |
52 |
Correct |
2 ms |
376 KB |
Output is correct |
53 |
Correct |
2 ms |
296 KB |
Output is correct |
54 |
Correct |
2 ms |
376 KB |
Output is correct |
55 |
Correct |
2 ms |
376 KB |
Output is correct |
56 |
Correct |
2 ms |
376 KB |
Output is correct |
57 |
Correct |
2 ms |
424 KB |
Output is correct |
58 |
Correct |
2 ms |
504 KB |
Output is correct |
59 |
Correct |
2 ms |
376 KB |
Output is correct |
60 |
Correct |
2 ms |
404 KB |
Output is correct |
61 |
Correct |
2 ms |
376 KB |
Output is correct |
62 |
Correct |
2 ms |
376 KB |
Output is correct |
63 |
Correct |
2 ms |
376 KB |
Output is correct |
64 |
Correct |
2 ms |
376 KB |
Output is correct |
65 |
Correct |
2 ms |
388 KB |
Output is correct |
66 |
Correct |
2 ms |
384 KB |
Output is correct |
67 |
Correct |
2 ms |
376 KB |
Output is correct |
68 |
Correct |
2 ms |
376 KB |
Output is correct |
69 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
380 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
420 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
376 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
380 KB |
Output is correct |
18 |
Correct |
2 ms |
348 KB |
Output is correct |
19 |
Correct |
2 ms |
376 KB |
Output is correct |
20 |
Correct |
2 ms |
376 KB |
Output is correct |
21 |
Correct |
2 ms |
376 KB |
Output is correct |
22 |
Correct |
2 ms |
424 KB |
Output is correct |
23 |
Correct |
2 ms |
384 KB |
Output is correct |
24 |
Correct |
2 ms |
380 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
376 KB |
Output is correct |
30 |
Correct |
2 ms |
376 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
376 KB |
Output is correct |
34 |
Correct |
2 ms |
376 KB |
Output is correct |
35 |
Correct |
2 ms |
376 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
376 KB |
Output is correct |
38 |
Correct |
2 ms |
376 KB |
Output is correct |
39 |
Correct |
2 ms |
376 KB |
Output is correct |
40 |
Correct |
2 ms |
376 KB |
Output is correct |
41 |
Correct |
2 ms |
376 KB |
Output is correct |
42 |
Correct |
2 ms |
376 KB |
Output is correct |
43 |
Correct |
2 ms |
376 KB |
Output is correct |
44 |
Correct |
2 ms |
376 KB |
Output is correct |
45 |
Correct |
2 ms |
376 KB |
Output is correct |
46 |
Correct |
2 ms |
376 KB |
Output is correct |
47 |
Correct |
2 ms |
376 KB |
Output is correct |
48 |
Correct |
2 ms |
376 KB |
Output is correct |
49 |
Correct |
2 ms |
376 KB |
Output is correct |
50 |
Correct |
2 ms |
376 KB |
Output is correct |
51 |
Correct |
2 ms |
388 KB |
Output is correct |
52 |
Correct |
2 ms |
376 KB |
Output is correct |
53 |
Correct |
2 ms |
296 KB |
Output is correct |
54 |
Correct |
2 ms |
376 KB |
Output is correct |
55 |
Correct |
2 ms |
376 KB |
Output is correct |
56 |
Correct |
2 ms |
376 KB |
Output is correct |
57 |
Correct |
2 ms |
424 KB |
Output is correct |
58 |
Correct |
2 ms |
504 KB |
Output is correct |
59 |
Correct |
2 ms |
376 KB |
Output is correct |
60 |
Correct |
2 ms |
404 KB |
Output is correct |
61 |
Correct |
2 ms |
376 KB |
Output is correct |
62 |
Correct |
2 ms |
376 KB |
Output is correct |
63 |
Correct |
2 ms |
376 KB |
Output is correct |
64 |
Correct |
2 ms |
376 KB |
Output is correct |
65 |
Correct |
2 ms |
388 KB |
Output is correct |
66 |
Correct |
2 ms |
384 KB |
Output is correct |
67 |
Correct |
2 ms |
376 KB |
Output is correct |
68 |
Correct |
2 ms |
376 KB |
Output is correct |
69 |
Correct |
2 ms |
376 KB |
Output is correct |
70 |
Correct |
3 ms |
588 KB |
Output is correct |
71 |
Correct |
2 ms |
376 KB |
Output is correct |
72 |
Correct |
2 ms |
376 KB |
Output is correct |
73 |
Correct |
2 ms |
380 KB |
Output is correct |
74 |
Correct |
2 ms |
376 KB |
Output is correct |
75 |
Correct |
2 ms |
376 KB |
Output is correct |
76 |
Correct |
2 ms |
376 KB |
Output is correct |
77 |
Correct |
3 ms |
380 KB |
Output is correct |
78 |
Correct |
2 ms |
384 KB |
Output is correct |
79 |
Correct |
2 ms |
376 KB |
Output is correct |
80 |
Correct |
2 ms |
504 KB |
Output is correct |
81 |
Correct |
2 ms |
376 KB |
Output is correct |
82 |
Correct |
2 ms |
376 KB |
Output is correct |
83 |
Correct |
2 ms |
376 KB |
Output is correct |
84 |
Correct |
3 ms |
432 KB |
Output is correct |
85 |
Correct |
2 ms |
376 KB |
Output is correct |
86 |
Correct |
2 ms |
376 KB |
Output is correct |
87 |
Correct |
2 ms |
376 KB |
Output is correct |
88 |
Correct |
2 ms |
480 KB |
Output is correct |
89 |
Correct |
2 ms |
376 KB |
Output is correct |
90 |
Correct |
3 ms |
376 KB |
Output is correct |
91 |
Correct |
2 ms |
376 KB |
Output is correct |
92 |
Correct |
2 ms |
376 KB |
Output is correct |
93 |
Correct |
2 ms |
380 KB |
Output is correct |
94 |
Correct |
2 ms |
376 KB |
Output is correct |
95 |
Correct |
2 ms |
376 KB |
Output is correct |
96 |
Correct |
3 ms |
504 KB |
Output is correct |
97 |
Correct |
3 ms |
376 KB |
Output is correct |
98 |
Correct |
3 ms |
504 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
3948 KB |
Output is correct |
2 |
Runtime error |
3 ms |
504 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
376 KB |
Output is correct |
2 |
Correct |
2 ms |
376 KB |
Output is correct |
3 |
Correct |
2 ms |
376 KB |
Output is correct |
4 |
Correct |
2 ms |
376 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
376 KB |
Output is correct |
7 |
Correct |
2 ms |
376 KB |
Output is correct |
8 |
Correct |
2 ms |
376 KB |
Output is correct |
9 |
Correct |
2 ms |
380 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
420 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
376 KB |
Output is correct |
14 |
Correct |
2 ms |
376 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
376 KB |
Output is correct |
17 |
Correct |
2 ms |
380 KB |
Output is correct |
18 |
Correct |
2 ms |
348 KB |
Output is correct |
19 |
Correct |
2 ms |
376 KB |
Output is correct |
20 |
Correct |
2 ms |
376 KB |
Output is correct |
21 |
Correct |
2 ms |
376 KB |
Output is correct |
22 |
Correct |
2 ms |
424 KB |
Output is correct |
23 |
Correct |
2 ms |
384 KB |
Output is correct |
24 |
Correct |
2 ms |
380 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
376 KB |
Output is correct |
30 |
Correct |
2 ms |
376 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
376 KB |
Output is correct |
34 |
Correct |
2 ms |
376 KB |
Output is correct |
35 |
Correct |
2 ms |
376 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
376 KB |
Output is correct |
38 |
Correct |
2 ms |
376 KB |
Output is correct |
39 |
Correct |
2 ms |
376 KB |
Output is correct |
40 |
Correct |
2 ms |
376 KB |
Output is correct |
41 |
Correct |
2 ms |
376 KB |
Output is correct |
42 |
Correct |
2 ms |
376 KB |
Output is correct |
43 |
Correct |
2 ms |
376 KB |
Output is correct |
44 |
Correct |
2 ms |
376 KB |
Output is correct |
45 |
Correct |
2 ms |
376 KB |
Output is correct |
46 |
Correct |
2 ms |
376 KB |
Output is correct |
47 |
Correct |
2 ms |
376 KB |
Output is correct |
48 |
Correct |
2 ms |
376 KB |
Output is correct |
49 |
Correct |
2 ms |
376 KB |
Output is correct |
50 |
Correct |
2 ms |
376 KB |
Output is correct |
51 |
Correct |
2 ms |
388 KB |
Output is correct |
52 |
Correct |
2 ms |
376 KB |
Output is correct |
53 |
Correct |
2 ms |
296 KB |
Output is correct |
54 |
Correct |
2 ms |
376 KB |
Output is correct |
55 |
Correct |
2 ms |
376 KB |
Output is correct |
56 |
Correct |
2 ms |
376 KB |
Output is correct |
57 |
Correct |
2 ms |
424 KB |
Output is correct |
58 |
Correct |
2 ms |
504 KB |
Output is correct |
59 |
Correct |
2 ms |
376 KB |
Output is correct |
60 |
Correct |
2 ms |
404 KB |
Output is correct |
61 |
Correct |
2 ms |
376 KB |
Output is correct |
62 |
Correct |
2 ms |
376 KB |
Output is correct |
63 |
Correct |
2 ms |
376 KB |
Output is correct |
64 |
Correct |
2 ms |
376 KB |
Output is correct |
65 |
Correct |
2 ms |
388 KB |
Output is correct |
66 |
Correct |
2 ms |
384 KB |
Output is correct |
67 |
Correct |
2 ms |
376 KB |
Output is correct |
68 |
Correct |
2 ms |
376 KB |
Output is correct |
69 |
Correct |
2 ms |
376 KB |
Output is correct |
70 |
Correct |
3 ms |
588 KB |
Output is correct |
71 |
Correct |
2 ms |
376 KB |
Output is correct |
72 |
Correct |
2 ms |
376 KB |
Output is correct |
73 |
Correct |
2 ms |
380 KB |
Output is correct |
74 |
Correct |
2 ms |
376 KB |
Output is correct |
75 |
Correct |
2 ms |
376 KB |
Output is correct |
76 |
Correct |
2 ms |
376 KB |
Output is correct |
77 |
Correct |
3 ms |
380 KB |
Output is correct |
78 |
Correct |
2 ms |
384 KB |
Output is correct |
79 |
Correct |
2 ms |
376 KB |
Output is correct |
80 |
Correct |
2 ms |
504 KB |
Output is correct |
81 |
Correct |
2 ms |
376 KB |
Output is correct |
82 |
Correct |
2 ms |
376 KB |
Output is correct |
83 |
Correct |
2 ms |
376 KB |
Output is correct |
84 |
Correct |
3 ms |
432 KB |
Output is correct |
85 |
Correct |
2 ms |
376 KB |
Output is correct |
86 |
Correct |
2 ms |
376 KB |
Output is correct |
87 |
Correct |
2 ms |
376 KB |
Output is correct |
88 |
Correct |
2 ms |
480 KB |
Output is correct |
89 |
Correct |
2 ms |
376 KB |
Output is correct |
90 |
Correct |
3 ms |
376 KB |
Output is correct |
91 |
Correct |
2 ms |
376 KB |
Output is correct |
92 |
Correct |
2 ms |
376 KB |
Output is correct |
93 |
Correct |
2 ms |
380 KB |
Output is correct |
94 |
Correct |
2 ms |
376 KB |
Output is correct |
95 |
Correct |
2 ms |
376 KB |
Output is correct |
96 |
Correct |
3 ms |
504 KB |
Output is correct |
97 |
Correct |
3 ms |
376 KB |
Output is correct |
98 |
Correct |
3 ms |
504 KB |
Output is correct |
99 |
Correct |
28 ms |
3948 KB |
Output is correct |
100 |
Runtime error |
3 ms |
504 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
101 |
Halted |
0 ms |
0 KB |
- |