#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e6+10;
const int inf = 1e9+10;
const int mod = 1e9+7;
int n;
int l[maxn], r[maxn];
int cor[maxn], comp[maxn];
int back[maxn];
int tree[2][4*maxn];
vector<int> one, zero;
void build(int node, int l, int r)
{
if (l == r)
{
tree[0][node] = inf;
tree[1][node] = -inf;
return;
}
int mid = (l+r)>>1;
build(2*node, l, mid); build(2*node+1, mid+1, r);
tree[0][node] = min(tree[0][2*node], tree[0][2*node+1]);
tree[1][node] = max(tree[1][2*node], tree[1][2*node+1]);
}
void upd(int node, int l, int r, int pos, int v, int k)
{
if (l == r)
{
tree[k][node] = v;
return;
}
int mid = (l+r)>>1;
if (pos <= mid) upd(2*node, l, mid, pos, v, k);
else upd(2*node+1, mid+1, r, pos, v, k);
tree[0][node] = min(tree[0][2*node], tree[0][2*node+1]);
tree[1][node] = max(tree[1][2*node], tree[1][2*node+1]);
}
int query(int node, int l, int r, int a, int b, int k)
{
if (l > b || r < a) return (k == 0 ? inf : -inf);
if (l >= a && r <= b) return tree[k][node];
int mid = (l+r)>>1;
int p1 = query(2*node, l, mid, a, b, k), p2 = query(2*node+1, mid+1, r, a, b, k);
if (!k) return min(p1, p2);
return max(p1, p2);
}
void dfs(int u, int C, int cc)
{
comp[u] = cc, cor[u] = C;
while (true)
{
int x = query(1, 1, 2*n, l[u]+1, r[u]-1, 0);
if (x >= l[u]) break;
upd(1, 1, 2*n, r[back[x]], inf, 0);
upd(1, 1, 2*n, l[back[x]], -inf, 1);
dfs(back[x], (!C ? 1 : 0), cc);
}
while (true)
{
int x = query(1, 1, 2*n, l[u]+1, r[u]-1, 1);
if (x <= r[u]) break;
upd(1, 1, 2*n, r[back[x]], inf, 0);
upd(1, 1, 2*n, l[back[x]], -inf, 1);
dfs(back[x], (!C ? 1 : 0), cc);
}
}
bool cmp(int a, int b)
{
return l[a] < l[b];
}
bool ok(bool k)
{
stack<int> stk;
if (!k)
{
for (auto i: zero)
{
while (stk.size() && l[i] > stk.top())
stk.pop();
if (stk.size() && stk.top() > l[i] && stk.top() < r[i])
return 0;
stk.push(r[i]);
}
}
else
{
for (auto i: one)
{
while (stk.size() && l[i] > stk.top())
stk.pop();
if (stk.size() && stk.top() > l[i] && stk.top() < r[i])
return 0;
stk.push(r[i]);
}
}
return 1;
}
int main(void)
{
scanf("%d", &n);
build(1, 1, 2*n);
for (int i = 1; i <= n; i++)
{
scanf("%d %d", &l[i], &r[i]);
back[l[i]] = back[r[i]] = i;
upd(1, 1, 2*n, r[i], l[i], 0);
upd(1, 1, 2*n, l[i], r[i], 1);
}
int cc = 0;
for (int i = 1; i <= n; i++)
{
if (!comp[i])
{
upd(1, 1, 2*n, r[i], inf, 0);
upd(1, 1, 2*n, l[i], -inf, 1);
dfs(i, 0, ++cc);
}
}
for (int i = 1; i <= n; i++)
{
if (cor[i] == 0) zero.push_back(i);
else one.push_back(i);
}
sort(zero.begin(), zero.end(), cmp);
sort(one.begin(), one.end(), cmp);
if (!ok(0) || !ok(1))
{
printf("0\n");
return 0;
}
int ans = 1;
for (int i = 1; i <= cc; i++)
ans = (ans*2)%mod;
printf("%d\n", ans);
}
Compilation message
port_facility.cpp: In function 'int main()':
port_facility.cpp:135:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &n);
~~~~~^~~~~~~~~~
port_facility.cpp:141:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &l[i], &r[i]);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
504 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 |
364 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
380 KB |
Output is correct |
12 |
Correct |
2 ms |
380 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 |
3 ms |
376 KB |
Output is correct |
18 |
Correct |
2 ms |
380 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 |
8 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
396 KB |
Output is correct |
24 |
Correct |
2 ms |
376 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
504 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 |
364 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
380 KB |
Output is correct |
12 |
Correct |
2 ms |
380 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 |
3 ms |
376 KB |
Output is correct |
18 |
Correct |
2 ms |
380 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 |
8 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
396 KB |
Output is correct |
24 |
Correct |
2 ms |
376 KB |
Output is correct |
25 |
Correct |
5 ms |
636 KB |
Output is correct |
26 |
Correct |
6 ms |
760 KB |
Output is correct |
27 |
Correct |
5 ms |
504 KB |
Output is correct |
28 |
Correct |
5 ms |
632 KB |
Output is correct |
29 |
Correct |
5 ms |
632 KB |
Output is correct |
30 |
Correct |
5 ms |
632 KB |
Output is correct |
31 |
Correct |
5 ms |
504 KB |
Output is correct |
32 |
Correct |
5 ms |
632 KB |
Output is correct |
33 |
Correct |
5 ms |
632 KB |
Output is correct |
34 |
Correct |
5 ms |
636 KB |
Output is correct |
35 |
Correct |
5 ms |
504 KB |
Output is correct |
36 |
Correct |
5 ms |
508 KB |
Output is correct |
37 |
Correct |
5 ms |
636 KB |
Output is correct |
38 |
Correct |
5 ms |
632 KB |
Output is correct |
39 |
Correct |
5 ms |
504 KB |
Output is correct |
40 |
Correct |
5 ms |
504 KB |
Output is correct |
41 |
Correct |
5 ms |
632 KB |
Output is correct |
42 |
Correct |
5 ms |
632 KB |
Output is correct |
43 |
Correct |
5 ms |
632 KB |
Output is correct |
44 |
Correct |
7 ms |
632 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
504 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 |
364 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
380 KB |
Output is correct |
12 |
Correct |
2 ms |
380 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 |
3 ms |
376 KB |
Output is correct |
18 |
Correct |
2 ms |
380 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 |
8 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
396 KB |
Output is correct |
24 |
Correct |
2 ms |
376 KB |
Output is correct |
25 |
Correct |
5 ms |
636 KB |
Output is correct |
26 |
Correct |
6 ms |
760 KB |
Output is correct |
27 |
Correct |
5 ms |
504 KB |
Output is correct |
28 |
Correct |
5 ms |
632 KB |
Output is correct |
29 |
Correct |
5 ms |
632 KB |
Output is correct |
30 |
Correct |
5 ms |
632 KB |
Output is correct |
31 |
Correct |
5 ms |
504 KB |
Output is correct |
32 |
Correct |
5 ms |
632 KB |
Output is correct |
33 |
Correct |
5 ms |
632 KB |
Output is correct |
34 |
Correct |
5 ms |
636 KB |
Output is correct |
35 |
Correct |
5 ms |
504 KB |
Output is correct |
36 |
Correct |
5 ms |
508 KB |
Output is correct |
37 |
Correct |
5 ms |
636 KB |
Output is correct |
38 |
Correct |
5 ms |
632 KB |
Output is correct |
39 |
Correct |
5 ms |
504 KB |
Output is correct |
40 |
Correct |
5 ms |
504 KB |
Output is correct |
41 |
Correct |
5 ms |
632 KB |
Output is correct |
42 |
Correct |
5 ms |
632 KB |
Output is correct |
43 |
Correct |
5 ms |
632 KB |
Output is correct |
44 |
Correct |
7 ms |
632 KB |
Output is correct |
45 |
Correct |
261 ms |
9868 KB |
Output is correct |
46 |
Correct |
277 ms |
10840 KB |
Output is correct |
47 |
Correct |
254 ms |
9204 KB |
Output is correct |
48 |
Correct |
273 ms |
10868 KB |
Output is correct |
49 |
Correct |
425 ms |
9332 KB |
Output is correct |
50 |
Correct |
258 ms |
10740 KB |
Output is correct |
51 |
Correct |
262 ms |
10484 KB |
Output is correct |
52 |
Correct |
205 ms |
8820 KB |
Output is correct |
53 |
Correct |
257 ms |
8940 KB |
Output is correct |
54 |
Correct |
283 ms |
16440 KB |
Output is correct |
55 |
Correct |
272 ms |
12680 KB |
Output is correct |
56 |
Correct |
366 ms |
12580 KB |
Output is correct |
57 |
Correct |
231 ms |
8792 KB |
Output is correct |
58 |
Correct |
220 ms |
8824 KB |
Output is correct |
59 |
Correct |
229 ms |
8824 KB |
Output is correct |
60 |
Correct |
253 ms |
8920 KB |
Output is correct |
61 |
Correct |
258 ms |
8788 KB |
Output is correct |
62 |
Correct |
233 ms |
8948 KB |
Output is correct |
63 |
Correct |
242 ms |
8816 KB |
Output is correct |
64 |
Correct |
250 ms |
8720 KB |
Output is correct |
65 |
Correct |
321 ms |
16520 KB |
Output is correct |
66 |
Correct |
328 ms |
16420 KB |
Output is correct |
67 |
Correct |
270 ms |
12596 KB |
Output is correct |
68 |
Correct |
285 ms |
12600 KB |
Output is correct |
69 |
Correct |
269 ms |
12316 KB |
Output is correct |
70 |
Correct |
266 ms |
12396 KB |
Output is correct |
71 |
Correct |
272 ms |
16524 KB |
Output is correct |
72 |
Correct |
271 ms |
16664 KB |
Output is correct |
73 |
Correct |
277 ms |
14148 KB |
Output is correct |
74 |
Correct |
285 ms |
14064 KB |
Output is correct |
75 |
Correct |
238 ms |
13316 KB |
Output is correct |
76 |
Correct |
238 ms |
16720 KB |
Output is correct |
77 |
Correct |
218 ms |
16484 KB |
Output is correct |
78 |
Correct |
264 ms |
10584 KB |
Output is correct |
79 |
Correct |
251 ms |
9972 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
504 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 |
364 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
380 KB |
Output is correct |
12 |
Correct |
2 ms |
380 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 |
3 ms |
376 KB |
Output is correct |
18 |
Correct |
2 ms |
380 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 |
8 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
396 KB |
Output is correct |
24 |
Correct |
2 ms |
376 KB |
Output is correct |
25 |
Correct |
5 ms |
636 KB |
Output is correct |
26 |
Correct |
6 ms |
760 KB |
Output is correct |
27 |
Correct |
5 ms |
504 KB |
Output is correct |
28 |
Correct |
5 ms |
632 KB |
Output is correct |
29 |
Correct |
5 ms |
632 KB |
Output is correct |
30 |
Correct |
5 ms |
632 KB |
Output is correct |
31 |
Correct |
5 ms |
504 KB |
Output is correct |
32 |
Correct |
5 ms |
632 KB |
Output is correct |
33 |
Correct |
5 ms |
632 KB |
Output is correct |
34 |
Correct |
5 ms |
636 KB |
Output is correct |
35 |
Correct |
5 ms |
504 KB |
Output is correct |
36 |
Correct |
5 ms |
508 KB |
Output is correct |
37 |
Correct |
5 ms |
636 KB |
Output is correct |
38 |
Correct |
5 ms |
632 KB |
Output is correct |
39 |
Correct |
5 ms |
504 KB |
Output is correct |
40 |
Correct |
5 ms |
504 KB |
Output is correct |
41 |
Correct |
5 ms |
632 KB |
Output is correct |
42 |
Correct |
5 ms |
632 KB |
Output is correct |
43 |
Correct |
5 ms |
632 KB |
Output is correct |
44 |
Correct |
7 ms |
632 KB |
Output is correct |
45 |
Correct |
261 ms |
9868 KB |
Output is correct |
46 |
Correct |
277 ms |
10840 KB |
Output is correct |
47 |
Correct |
254 ms |
9204 KB |
Output is correct |
48 |
Correct |
273 ms |
10868 KB |
Output is correct |
49 |
Correct |
425 ms |
9332 KB |
Output is correct |
50 |
Correct |
258 ms |
10740 KB |
Output is correct |
51 |
Correct |
262 ms |
10484 KB |
Output is correct |
52 |
Correct |
205 ms |
8820 KB |
Output is correct |
53 |
Correct |
257 ms |
8940 KB |
Output is correct |
54 |
Correct |
283 ms |
16440 KB |
Output is correct |
55 |
Correct |
272 ms |
12680 KB |
Output is correct |
56 |
Correct |
366 ms |
12580 KB |
Output is correct |
57 |
Correct |
231 ms |
8792 KB |
Output is correct |
58 |
Correct |
220 ms |
8824 KB |
Output is correct |
59 |
Correct |
229 ms |
8824 KB |
Output is correct |
60 |
Correct |
253 ms |
8920 KB |
Output is correct |
61 |
Correct |
258 ms |
8788 KB |
Output is correct |
62 |
Correct |
233 ms |
8948 KB |
Output is correct |
63 |
Correct |
242 ms |
8816 KB |
Output is correct |
64 |
Correct |
250 ms |
8720 KB |
Output is correct |
65 |
Correct |
321 ms |
16520 KB |
Output is correct |
66 |
Correct |
328 ms |
16420 KB |
Output is correct |
67 |
Correct |
270 ms |
12596 KB |
Output is correct |
68 |
Correct |
285 ms |
12600 KB |
Output is correct |
69 |
Correct |
269 ms |
12316 KB |
Output is correct |
70 |
Correct |
266 ms |
12396 KB |
Output is correct |
71 |
Correct |
272 ms |
16524 KB |
Output is correct |
72 |
Correct |
271 ms |
16664 KB |
Output is correct |
73 |
Correct |
277 ms |
14148 KB |
Output is correct |
74 |
Correct |
285 ms |
14064 KB |
Output is correct |
75 |
Correct |
238 ms |
13316 KB |
Output is correct |
76 |
Correct |
238 ms |
16720 KB |
Output is correct |
77 |
Correct |
218 ms |
16484 KB |
Output is correct |
78 |
Correct |
264 ms |
10584 KB |
Output is correct |
79 |
Correct |
251 ms |
9972 KB |
Output is correct |
80 |
Correct |
3748 ms |
81756 KB |
Output is correct |
81 |
Correct |
3840 ms |
80992 KB |
Output is correct |
82 |
Correct |
3604 ms |
77744 KB |
Output is correct |
83 |
Correct |
3630 ms |
80980 KB |
Output is correct |
84 |
Correct |
3653 ms |
82000 KB |
Output is correct |
85 |
Correct |
3685 ms |
78612 KB |
Output is correct |
86 |
Correct |
3640 ms |
81236 KB |
Output is correct |
87 |
Correct |
2831 ms |
75488 KB |
Output is correct |
88 |
Correct |
3969 ms |
79392 KB |
Output is correct |
89 |
Correct |
3996 ms |
153876 KB |
Output is correct |
90 |
Correct |
4008 ms |
114612 KB |
Output is correct |
91 |
Correct |
3988 ms |
114516 KB |
Output is correct |
92 |
Correct |
3130 ms |
76188 KB |
Output is correct |
93 |
Correct |
2934 ms |
75564 KB |
Output is correct |
94 |
Correct |
3508 ms |
76508 KB |
Output is correct |
95 |
Correct |
3499 ms |
76588 KB |
Output is correct |
96 |
Correct |
3470 ms |
77020 KB |
Output is correct |
97 |
Correct |
3296 ms |
76300 KB |
Output is correct |
98 |
Correct |
3532 ms |
76616 KB |
Output is correct |
99 |
Correct |
3480 ms |
76980 KB |
Output is correct |
100 |
Correct |
5320 ms |
153612 KB |
Output is correct |
101 |
Correct |
5172 ms |
153820 KB |
Output is correct |
102 |
Correct |
3977 ms |
116504 KB |
Output is correct |
103 |
Correct |
3916 ms |
116536 KB |
Output is correct |
104 |
Correct |
3914 ms |
112964 KB |
Output is correct |
105 |
Correct |
4122 ms |
112992 KB |
Output is correct |
106 |
Correct |
4078 ms |
155560 KB |
Output is correct |
107 |
Correct |
4203 ms |
155592 KB |
Output is correct |
108 |
Correct |
3863 ms |
130316 KB |
Output is correct |
109 |
Correct |
3876 ms |
130340 KB |
Output is correct |
110 |
Correct |
3205 ms |
152168 KB |
Output is correct |
111 |
Correct |
3197 ms |
153652 KB |
Output is correct |
112 |
Correct |
3248 ms |
153872 KB |
Output is correct |
113 |
Correct |
3592 ms |
77760 KB |
Output is correct |
114 |
Correct |
3610 ms |
80772 KB |
Output is correct |