#include <bits/stdc++.h>
using namespace std;
vector<long long> v;
vector<pair<long long,long long> > V;
int n,l[505],r[505],F[2][2005][505],mod,tinh[505],tinh2[2005][505];
long long lt(long long x,long long y)
{
if (y==0) return 1;
long long k=lt(x,y/2);
if (y%2) return k*k%mod*x%mod;
return k*k%mod;
}
int main()
{
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin>>n;
for (int i=1;i<=n;++i)
{
cin>>l[i]>>r[i];
v.push_back(l[i]);
v.push_back(r[i]);
}
sort(v.begin(),v.end());
v.resize(unique(v.begin(),v.end())-v.begin());
long long ct=1;
for (int i=0;i<v.size();++i)
{
if (ct<v[i]) V.push_back({ct,v[i]-ct});
ct=v[i]+1;
V.push_back({v[i],1});
}
for (int i=0;i<V.size();++i) F[0][i][0]=1;
F[1][0][0]=1;
ct=0;mod=1e9+7;
for (int i=1;i<=500;++i) tinh[i]=lt(i,mod-2);
for (int j=0;j<V.size();++j)
for (int k=1;k<=n;++k) tinh2[j][k]=tinh[k]*(V[j].second-k+1)%mod;
for (int i=1;i<=n;++i)
{
ct=1-ct;
pair<long long,long long> X={l[i],0LL};
l[i]=lower_bound(V.begin(),V.end(),X)-V.begin();
X={r[i],0LL};
r[i]=lower_bound(V.begin(),V.end(),X)-V.begin();
for (int j=0;j<V.size();++j)
{
if (j) F[ct][j][0]=0;
if (j) for (int k=0;k<=min(1LL*i,V[j-1].second);++k)
{
F[ct][j][0]+=F[ct][j-1][k];
if (F[ct][j][0]>=mod) F[ct][j][0]-=mod;
}
for (int k=1;k<=min(1LL*i,V[j].second);++k)
{
F[ct][j][k]=F[1-ct][j][k];
if (j>=l[i] && j<=r[i]){
long long X=F[1-ct][j][k-1];
X=X*tinh2[j][k]%mod;
F[ct][j][k]+=X;
if (F[ct][j][k]>=mod) F[ct][j][k]-=mod;
}
}
}
}
long long kq=mod-1;
for (int k=0;k<=n;++k) {kq=(kq+F[ct][V.size()-1][k]);if (kq>=mod) kq-=mod;}
cout<<kq;
return 0;
}
Compilation message
boat.cpp: In function 'long long int lt(long long int, long long int)':
boat.cpp:11:5: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
11 | if (y%2) return k*k%mod*x%mod;
| ^~
boat.cpp:12:14: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
12 | return k*k%mod;
| ^~~~~~
boat.cpp: In function 'int main()':
boat.cpp:28:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
28 | for (int i=0;i<v.size();++i)
| ~^~~~~~~~~
boat.cpp:35:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
35 | for (int i=0;i<V.size();++i) F[0][i][0]=1;
| ~^~~~~~~~~
boat.cpp:41:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
41 | for (int j=0;j<V.size();++j)
| ~^~~~~~~~~
boat.cpp:51:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
51 | for (int j=0;j<V.size();++j)
| ~^~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
162 ms |
6508 KB |
Output is correct |
2 |
Correct |
162 ms |
6380 KB |
Output is correct |
3 |
Correct |
183 ms |
6508 KB |
Output is correct |
4 |
Correct |
167 ms |
6508 KB |
Output is correct |
5 |
Correct |
169 ms |
6380 KB |
Output is correct |
6 |
Correct |
162 ms |
6508 KB |
Output is correct |
7 |
Correct |
166 ms |
6380 KB |
Output is correct |
8 |
Correct |
167 ms |
6380 KB |
Output is correct |
9 |
Correct |
164 ms |
6380 KB |
Output is correct |
10 |
Correct |
167 ms |
6508 KB |
Output is correct |
11 |
Correct |
165 ms |
6380 KB |
Output is correct |
12 |
Correct |
168 ms |
6380 KB |
Output is correct |
13 |
Correct |
166 ms |
6380 KB |
Output is correct |
14 |
Correct |
167 ms |
6508 KB |
Output is correct |
15 |
Correct |
162 ms |
6380 KB |
Output is correct |
16 |
Correct |
29 ms |
1388 KB |
Output is correct |
17 |
Correct |
38 ms |
1516 KB |
Output is correct |
18 |
Correct |
30 ms |
1516 KB |
Output is correct |
19 |
Correct |
32 ms |
1516 KB |
Output is correct |
20 |
Correct |
32 ms |
1516 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
162 ms |
6508 KB |
Output is correct |
2 |
Correct |
162 ms |
6380 KB |
Output is correct |
3 |
Correct |
183 ms |
6508 KB |
Output is correct |
4 |
Correct |
167 ms |
6508 KB |
Output is correct |
5 |
Correct |
169 ms |
6380 KB |
Output is correct |
6 |
Correct |
162 ms |
6508 KB |
Output is correct |
7 |
Correct |
166 ms |
6380 KB |
Output is correct |
8 |
Correct |
167 ms |
6380 KB |
Output is correct |
9 |
Correct |
164 ms |
6380 KB |
Output is correct |
10 |
Correct |
167 ms |
6508 KB |
Output is correct |
11 |
Correct |
165 ms |
6380 KB |
Output is correct |
12 |
Correct |
168 ms |
6380 KB |
Output is correct |
13 |
Correct |
166 ms |
6380 KB |
Output is correct |
14 |
Correct |
167 ms |
6508 KB |
Output is correct |
15 |
Correct |
162 ms |
6380 KB |
Output is correct |
16 |
Correct |
29 ms |
1388 KB |
Output is correct |
17 |
Correct |
38 ms |
1516 KB |
Output is correct |
18 |
Correct |
30 ms |
1516 KB |
Output is correct |
19 |
Correct |
32 ms |
1516 KB |
Output is correct |
20 |
Correct |
32 ms |
1516 KB |
Output is correct |
21 |
Correct |
35 ms |
10348 KB |
Output is correct |
22 |
Correct |
37 ms |
10564 KB |
Output is correct |
23 |
Correct |
39 ms |
10220 KB |
Output is correct |
24 |
Correct |
36 ms |
10476 KB |
Output is correct |
25 |
Correct |
36 ms |
10220 KB |
Output is correct |
26 |
Correct |
31 ms |
9708 KB |
Output is correct |
27 |
Correct |
41 ms |
9836 KB |
Output is correct |
28 |
Correct |
33 ms |
9836 KB |
Output is correct |
29 |
Correct |
31 ms |
9836 KB |
Output is correct |
30 |
Correct |
174 ms |
11372 KB |
Output is correct |
31 |
Correct |
175 ms |
11372 KB |
Output is correct |
32 |
Correct |
181 ms |
11500 KB |
Output is correct |
33 |
Correct |
179 ms |
11500 KB |
Output is correct |
34 |
Correct |
190 ms |
11500 KB |
Output is correct |
35 |
Correct |
164 ms |
6508 KB |
Output is correct |
36 |
Correct |
155 ms |
6508 KB |
Output is correct |
37 |
Correct |
172 ms |
6380 KB |
Output is correct |
38 |
Correct |
156 ms |
6508 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
7 ms |
2796 KB |
Output is correct |
2 |
Correct |
7 ms |
2796 KB |
Output is correct |
3 |
Correct |
7 ms |
2796 KB |
Output is correct |
4 |
Correct |
7 ms |
2796 KB |
Output is correct |
5 |
Correct |
8 ms |
2796 KB |
Output is correct |
6 |
Correct |
9 ms |
2796 KB |
Output is correct |
7 |
Correct |
9 ms |
2796 KB |
Output is correct |
8 |
Correct |
9 ms |
2796 KB |
Output is correct |
9 |
Correct |
9 ms |
2796 KB |
Output is correct |
10 |
Correct |
9 ms |
2796 KB |
Output is correct |
11 |
Correct |
7 ms |
2796 KB |
Output is correct |
12 |
Correct |
7 ms |
2816 KB |
Output is correct |
13 |
Correct |
7 ms |
2796 KB |
Output is correct |
14 |
Correct |
7 ms |
2924 KB |
Output is correct |
15 |
Correct |
7 ms |
2796 KB |
Output is correct |
16 |
Correct |
3 ms |
1388 KB |
Output is correct |
17 |
Correct |
3 ms |
1388 KB |
Output is correct |
18 |
Correct |
4 ms |
1388 KB |
Output is correct |
19 |
Correct |
4 ms |
1388 KB |
Output is correct |
20 |
Correct |
4 ms |
1388 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
162 ms |
6508 KB |
Output is correct |
2 |
Correct |
162 ms |
6380 KB |
Output is correct |
3 |
Correct |
183 ms |
6508 KB |
Output is correct |
4 |
Correct |
167 ms |
6508 KB |
Output is correct |
5 |
Correct |
169 ms |
6380 KB |
Output is correct |
6 |
Correct |
162 ms |
6508 KB |
Output is correct |
7 |
Correct |
166 ms |
6380 KB |
Output is correct |
8 |
Correct |
167 ms |
6380 KB |
Output is correct |
9 |
Correct |
164 ms |
6380 KB |
Output is correct |
10 |
Correct |
167 ms |
6508 KB |
Output is correct |
11 |
Correct |
165 ms |
6380 KB |
Output is correct |
12 |
Correct |
168 ms |
6380 KB |
Output is correct |
13 |
Correct |
166 ms |
6380 KB |
Output is correct |
14 |
Correct |
167 ms |
6508 KB |
Output is correct |
15 |
Correct |
162 ms |
6380 KB |
Output is correct |
16 |
Correct |
29 ms |
1388 KB |
Output is correct |
17 |
Correct |
38 ms |
1516 KB |
Output is correct |
18 |
Correct |
30 ms |
1516 KB |
Output is correct |
19 |
Correct |
32 ms |
1516 KB |
Output is correct |
20 |
Correct |
32 ms |
1516 KB |
Output is correct |
21 |
Correct |
35 ms |
10348 KB |
Output is correct |
22 |
Correct |
37 ms |
10564 KB |
Output is correct |
23 |
Correct |
39 ms |
10220 KB |
Output is correct |
24 |
Correct |
36 ms |
10476 KB |
Output is correct |
25 |
Correct |
36 ms |
10220 KB |
Output is correct |
26 |
Correct |
31 ms |
9708 KB |
Output is correct |
27 |
Correct |
41 ms |
9836 KB |
Output is correct |
28 |
Correct |
33 ms |
9836 KB |
Output is correct |
29 |
Correct |
31 ms |
9836 KB |
Output is correct |
30 |
Correct |
174 ms |
11372 KB |
Output is correct |
31 |
Correct |
175 ms |
11372 KB |
Output is correct |
32 |
Correct |
181 ms |
11500 KB |
Output is correct |
33 |
Correct |
179 ms |
11500 KB |
Output is correct |
34 |
Correct |
190 ms |
11500 KB |
Output is correct |
35 |
Correct |
164 ms |
6508 KB |
Output is correct |
36 |
Correct |
155 ms |
6508 KB |
Output is correct |
37 |
Correct |
172 ms |
6380 KB |
Output is correct |
38 |
Correct |
156 ms |
6508 KB |
Output is correct |
39 |
Correct |
7 ms |
2796 KB |
Output is correct |
40 |
Correct |
7 ms |
2796 KB |
Output is correct |
41 |
Correct |
7 ms |
2796 KB |
Output is correct |
42 |
Correct |
7 ms |
2796 KB |
Output is correct |
43 |
Correct |
8 ms |
2796 KB |
Output is correct |
44 |
Correct |
9 ms |
2796 KB |
Output is correct |
45 |
Correct |
9 ms |
2796 KB |
Output is correct |
46 |
Correct |
9 ms |
2796 KB |
Output is correct |
47 |
Correct |
9 ms |
2796 KB |
Output is correct |
48 |
Correct |
9 ms |
2796 KB |
Output is correct |
49 |
Correct |
7 ms |
2796 KB |
Output is correct |
50 |
Correct |
7 ms |
2816 KB |
Output is correct |
51 |
Correct |
7 ms |
2796 KB |
Output is correct |
52 |
Correct |
7 ms |
2924 KB |
Output is correct |
53 |
Correct |
7 ms |
2796 KB |
Output is correct |
54 |
Correct |
3 ms |
1388 KB |
Output is correct |
55 |
Correct |
3 ms |
1388 KB |
Output is correct |
56 |
Correct |
4 ms |
1388 KB |
Output is correct |
57 |
Correct |
4 ms |
1388 KB |
Output is correct |
58 |
Correct |
4 ms |
1388 KB |
Output is correct |
59 |
Correct |
667 ms |
12268 KB |
Output is correct |
60 |
Correct |
656 ms |
12396 KB |
Output is correct |
61 |
Correct |
644 ms |
12336 KB |
Output is correct |
62 |
Correct |
687 ms |
12396 KB |
Output is correct |
63 |
Correct |
675 ms |
12396 KB |
Output is correct |
64 |
Correct |
899 ms |
12336 KB |
Output is correct |
65 |
Correct |
903 ms |
12396 KB |
Output is correct |
66 |
Correct |
910 ms |
12336 KB |
Output is correct |
67 |
Correct |
893 ms |
12396 KB |
Output is correct |
68 |
Correct |
890 ms |
12396 KB |
Output is correct |
69 |
Correct |
618 ms |
12268 KB |
Output is correct |
70 |
Correct |
613 ms |
12268 KB |
Output is correct |
71 |
Correct |
619 ms |
12336 KB |
Output is correct |
72 |
Correct |
633 ms |
12396 KB |
Output is correct |
73 |
Correct |
636 ms |
12396 KB |
Output is correct |
74 |
Correct |
62 ms |
1644 KB |
Output is correct |
75 |
Correct |
70 ms |
1644 KB |
Output is correct |
76 |
Correct |
70 ms |
1644 KB |
Output is correct |
77 |
Correct |
61 ms |
1644 KB |
Output is correct |
78 |
Correct |
62 ms |
1644 KB |
Output is correct |