#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll mod=1e9+7;
const ll MAXN=1024;
ll dp[MAXN][2*MAXN];
ll l1[2*MAXN],r1[2*MAXN];
ll n;
ll a[MAXN],b[MAXN];
ll a1[MAXN],b1[MAXN];
ll inv[MAXN];
ll fastpow(ll x,ll p)
{
if(p==0)return 1;
ll t=fastpow(x,p/2);
t*=t;t%=mod;
if(p%2==1)t*=x;
t%=mod;
return t;
}
int main()
{
cin>>n;
vector<ll>v;
for(int i=1;i<=n;i++)
{
cin>>a[i]>>b[i];
v.push_back(a[i]);
v.push_back(b[i]+1);
}
sort(v.begin(),v.end());
int cnt=0;
for(int i=1;i<v.size();i++)
{
if(v[i]==v[i-1])continue;
cnt++;
l1[cnt]=v[i-1];
r1[cnt]=v[i]-1;
}
for(int i=0;i<2*MAXN;i++)
{
dp[0][i]=1;
}
for(int i=1;i<MAXN;i++)inv[i]=fastpow(i,mod-2);
for(int i=1;i<=cnt;i++)
{
ll t=r1[i]-l1[i]+1;
for(int j=1;j<=n;j++)
{
dp[j][i]=dp[j][i-1];
if(a[j]>r1[i]||b[j]<l1[i])continue;
ll fnaf=t,c=1;
for(int k=j-1;k>=0;k--)
{
dp[j][i]=dp[j][i]+dp[k][i-1]*fnaf;
dp[j][i]%=mod;
if(a[k]<=l1[i]&&b[k]>=r1[i])
{
fnaf=fnaf*(t+c);
fnaf%=mod;
c++;
fnaf*=inv[c];
fnaf%=mod;
}
}
}
}
ll ans=0;
for(ll i=1;i<=n;i++)
{
ans+=dp[i][cnt];ans%=mod;
}
cout<<ans<<endl;
return 0;
}
Compilation message
boat.cpp: In function 'int main()':
boat.cpp:33:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
33 | for(int i=1;i<v.size();i++)
| ~^~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
10 ms |
6380 KB |
Output is correct |
2 |
Correct |
10 ms |
6380 KB |
Output is correct |
3 |
Correct |
10 ms |
6380 KB |
Output is correct |
4 |
Correct |
10 ms |
6380 KB |
Output is correct |
5 |
Correct |
10 ms |
6380 KB |
Output is correct |
6 |
Correct |
10 ms |
6380 KB |
Output is correct |
7 |
Correct |
10 ms |
6380 KB |
Output is correct |
8 |
Correct |
10 ms |
6380 KB |
Output is correct |
9 |
Correct |
10 ms |
6380 KB |
Output is correct |
10 |
Correct |
11 ms |
6380 KB |
Output is correct |
11 |
Correct |
10 ms |
6380 KB |
Output is correct |
12 |
Correct |
10 ms |
6400 KB |
Output is correct |
13 |
Correct |
10 ms |
6392 KB |
Output is correct |
14 |
Correct |
10 ms |
6380 KB |
Output is correct |
15 |
Correct |
10 ms |
6380 KB |
Output is correct |
16 |
Correct |
5 ms |
2412 KB |
Output is correct |
17 |
Correct |
5 ms |
2412 KB |
Output is correct |
18 |
Correct |
6 ms |
2412 KB |
Output is correct |
19 |
Correct |
5 ms |
2412 KB |
Output is correct |
20 |
Correct |
5 ms |
2412 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
10 ms |
6380 KB |
Output is correct |
2 |
Correct |
10 ms |
6380 KB |
Output is correct |
3 |
Correct |
10 ms |
6380 KB |
Output is correct |
4 |
Correct |
10 ms |
6380 KB |
Output is correct |
5 |
Correct |
10 ms |
6380 KB |
Output is correct |
6 |
Correct |
10 ms |
6380 KB |
Output is correct |
7 |
Correct |
10 ms |
6380 KB |
Output is correct |
8 |
Correct |
10 ms |
6380 KB |
Output is correct |
9 |
Correct |
10 ms |
6380 KB |
Output is correct |
10 |
Correct |
11 ms |
6380 KB |
Output is correct |
11 |
Correct |
10 ms |
6380 KB |
Output is correct |
12 |
Correct |
10 ms |
6400 KB |
Output is correct |
13 |
Correct |
10 ms |
6392 KB |
Output is correct |
14 |
Correct |
10 ms |
6380 KB |
Output is correct |
15 |
Correct |
10 ms |
6380 KB |
Output is correct |
16 |
Correct |
5 ms |
2412 KB |
Output is correct |
17 |
Correct |
5 ms |
2412 KB |
Output is correct |
18 |
Correct |
6 ms |
2412 KB |
Output is correct |
19 |
Correct |
5 ms |
2412 KB |
Output is correct |
20 |
Correct |
5 ms |
2412 KB |
Output is correct |
21 |
Correct |
473 ms |
6440 KB |
Output is correct |
22 |
Correct |
412 ms |
6380 KB |
Output is correct |
23 |
Correct |
377 ms |
6508 KB |
Output is correct |
24 |
Correct |
408 ms |
6380 KB |
Output is correct |
25 |
Correct |
403 ms |
6380 KB |
Output is correct |
26 |
Correct |
720 ms |
6508 KB |
Output is correct |
27 |
Correct |
726 ms |
6380 KB |
Output is correct |
28 |
Correct |
695 ms |
6400 KB |
Output is correct |
29 |
Correct |
695 ms |
6508 KB |
Output is correct |
30 |
Correct |
12 ms |
6508 KB |
Output is correct |
31 |
Correct |
13 ms |
6380 KB |
Output is correct |
32 |
Correct |
14 ms |
6380 KB |
Output is correct |
33 |
Correct |
12 ms |
6380 KB |
Output is correct |
34 |
Correct |
13 ms |
6380 KB |
Output is correct |
35 |
Correct |
13 ms |
6412 KB |
Output is correct |
36 |
Correct |
13 ms |
6380 KB |
Output is correct |
37 |
Correct |
12 ms |
6380 KB |
Output is correct |
38 |
Correct |
13 ms |
6380 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
748 KB |
Output is correct |
2 |
Correct |
3 ms |
748 KB |
Output is correct |
3 |
Correct |
3 ms |
748 KB |
Output is correct |
4 |
Correct |
4 ms |
748 KB |
Output is correct |
5 |
Correct |
4 ms |
748 KB |
Output is correct |
6 |
Correct |
6 ms |
748 KB |
Output is correct |
7 |
Correct |
6 ms |
748 KB |
Output is correct |
8 |
Correct |
6 ms |
748 KB |
Output is correct |
9 |
Correct |
6 ms |
748 KB |
Output is correct |
10 |
Correct |
6 ms |
748 KB |
Output is correct |
11 |
Correct |
4 ms |
748 KB |
Output is correct |
12 |
Correct |
3 ms |
876 KB |
Output is correct |
13 |
Correct |
4 ms |
896 KB |
Output is correct |
14 |
Correct |
3 ms |
764 KB |
Output is correct |
15 |
Correct |
4 ms |
748 KB |
Output is correct |
16 |
Correct |
3 ms |
748 KB |
Output is correct |
17 |
Correct |
3 ms |
748 KB |
Output is correct |
18 |
Correct |
3 ms |
748 KB |
Output is correct |
19 |
Correct |
3 ms |
748 KB |
Output is correct |
20 |
Correct |
3 ms |
748 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
10 ms |
6380 KB |
Output is correct |
2 |
Correct |
10 ms |
6380 KB |
Output is correct |
3 |
Correct |
10 ms |
6380 KB |
Output is correct |
4 |
Correct |
10 ms |
6380 KB |
Output is correct |
5 |
Correct |
10 ms |
6380 KB |
Output is correct |
6 |
Correct |
10 ms |
6380 KB |
Output is correct |
7 |
Correct |
10 ms |
6380 KB |
Output is correct |
8 |
Correct |
10 ms |
6380 KB |
Output is correct |
9 |
Correct |
10 ms |
6380 KB |
Output is correct |
10 |
Correct |
11 ms |
6380 KB |
Output is correct |
11 |
Correct |
10 ms |
6380 KB |
Output is correct |
12 |
Correct |
10 ms |
6400 KB |
Output is correct |
13 |
Correct |
10 ms |
6392 KB |
Output is correct |
14 |
Correct |
10 ms |
6380 KB |
Output is correct |
15 |
Correct |
10 ms |
6380 KB |
Output is correct |
16 |
Correct |
5 ms |
2412 KB |
Output is correct |
17 |
Correct |
5 ms |
2412 KB |
Output is correct |
18 |
Correct |
6 ms |
2412 KB |
Output is correct |
19 |
Correct |
5 ms |
2412 KB |
Output is correct |
20 |
Correct |
5 ms |
2412 KB |
Output is correct |
21 |
Correct |
473 ms |
6440 KB |
Output is correct |
22 |
Correct |
412 ms |
6380 KB |
Output is correct |
23 |
Correct |
377 ms |
6508 KB |
Output is correct |
24 |
Correct |
408 ms |
6380 KB |
Output is correct |
25 |
Correct |
403 ms |
6380 KB |
Output is correct |
26 |
Correct |
720 ms |
6508 KB |
Output is correct |
27 |
Correct |
726 ms |
6380 KB |
Output is correct |
28 |
Correct |
695 ms |
6400 KB |
Output is correct |
29 |
Correct |
695 ms |
6508 KB |
Output is correct |
30 |
Correct |
12 ms |
6508 KB |
Output is correct |
31 |
Correct |
13 ms |
6380 KB |
Output is correct |
32 |
Correct |
14 ms |
6380 KB |
Output is correct |
33 |
Correct |
12 ms |
6380 KB |
Output is correct |
34 |
Correct |
13 ms |
6380 KB |
Output is correct |
35 |
Correct |
13 ms |
6412 KB |
Output is correct |
36 |
Correct |
13 ms |
6380 KB |
Output is correct |
37 |
Correct |
12 ms |
6380 KB |
Output is correct |
38 |
Correct |
13 ms |
6380 KB |
Output is correct |
39 |
Correct |
3 ms |
748 KB |
Output is correct |
40 |
Correct |
3 ms |
748 KB |
Output is correct |
41 |
Correct |
3 ms |
748 KB |
Output is correct |
42 |
Correct |
4 ms |
748 KB |
Output is correct |
43 |
Correct |
4 ms |
748 KB |
Output is correct |
44 |
Correct |
6 ms |
748 KB |
Output is correct |
45 |
Correct |
6 ms |
748 KB |
Output is correct |
46 |
Correct |
6 ms |
748 KB |
Output is correct |
47 |
Correct |
6 ms |
748 KB |
Output is correct |
48 |
Correct |
6 ms |
748 KB |
Output is correct |
49 |
Correct |
4 ms |
748 KB |
Output is correct |
50 |
Correct |
3 ms |
876 KB |
Output is correct |
51 |
Correct |
4 ms |
896 KB |
Output is correct |
52 |
Correct |
3 ms |
764 KB |
Output is correct |
53 |
Correct |
4 ms |
748 KB |
Output is correct |
54 |
Correct |
3 ms |
748 KB |
Output is correct |
55 |
Correct |
3 ms |
748 KB |
Output is correct |
56 |
Correct |
3 ms |
748 KB |
Output is correct |
57 |
Correct |
3 ms |
748 KB |
Output is correct |
58 |
Correct |
3 ms |
748 KB |
Output is correct |
59 |
Correct |
453 ms |
6508 KB |
Output is correct |
60 |
Correct |
458 ms |
6508 KB |
Output is correct |
61 |
Correct |
399 ms |
6380 KB |
Output is correct |
62 |
Correct |
471 ms |
6508 KB |
Output is correct |
63 |
Correct |
478 ms |
6508 KB |
Output is correct |
64 |
Correct |
803 ms |
6380 KB |
Output is correct |
65 |
Correct |
816 ms |
6612 KB |
Output is correct |
66 |
Correct |
798 ms |
6508 KB |
Output is correct |
67 |
Correct |
810 ms |
6404 KB |
Output is correct |
68 |
Correct |
802 ms |
6636 KB |
Output is correct |
69 |
Correct |
342 ms |
6508 KB |
Output is correct |
70 |
Correct |
326 ms |
6380 KB |
Output is correct |
71 |
Correct |
331 ms |
6508 KB |
Output is correct |
72 |
Correct |
347 ms |
6508 KB |
Output is correct |
73 |
Correct |
352 ms |
6380 KB |
Output is correct |
74 |
Correct |
90 ms |
2412 KB |
Output is correct |
75 |
Correct |
99 ms |
2412 KB |
Output is correct |
76 |
Correct |
94 ms |
2412 KB |
Output is correct |
77 |
Correct |
89 ms |
2412 KB |
Output is correct |
78 |
Correct |
105 ms |
2412 KB |
Output is correct |