#include<bits/stdc++.h>
using namespace std;
#define int long long
#define pll pair<int,int>
#define fi first
#define se second
const int mod=(int)1e9+7;
const int maxn=2*505;
int sz,a[maxn],b[maxn];
vector<int>v,s;
int n;
vector<pll>block;
int val[maxn][maxn];
int cnt[maxn];
int add[maxn];
int chia[maxn];
int pw(int x,int y)
{
if(y==0) return 1;
int x1=pw(x,y/2);
x1=x1*x1%mod;
if(y&1) x1=x1*x%mod;
return x1;
}
int pre[maxn];
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin >> n;
for(int i=1; i<=n; i++)
{
cin >> a[i] >> b[i];
v.push_back(a[i]-1);
v.push_back(b[i]);
}
for(int i=1;i<=n;i++) chia[i]=pw(i,mod-2);
sort(v.begin(),v.end());
for(int i=0;i<v.size();i++)
{
if(i==0||v[i]!=v[i-1]) s.push_back(v[i]);
}
swap(v,s);
for(int i=0;i<v.size();i++)
{
if(i==0) block.push_back({0,v[i]});
else block.push_back({v[i-1]+1,v[i]});
}
for(int i=0;i<block.size();i++) pre[i]=1;
int tt=0,valcu;
for(int i=1;i<=n;i++)
{
a[i]=lower_bound(block.begin(),block.end(),(pll){a[i]+1,0ll})-block.begin()-1;
b[i]=lower_bound(block.begin(),block.end(),(pll){b[i]+1,0ll})-block.begin()-1;
for(int j=a[i];j<=b[i];j++)
{
cnt[j]++;
val[j][cnt[j]]=pre[j-1];
for(int k=1;k<=cnt[j];k++)
{
tt=cnt[j]-k+1;
valcu=val[j][k]*(block[j].se-block[j].fi)%mod*chia[tt]%mod;
val[j][k]+=valcu;
if(k==cnt[j]) valcu=0;
if(val[j][k]>=mod) val[j][k]-=mod;
add[j]+=valcu;
if(add[j]>=mod) add[j]-=mod;
}
add[j]+=val[j][cnt[j]];
if(add[j]>=mod) add[j]-=mod;
}
for(int j=1;j<block.size();j++)
{
add[j]+=add[j-1];
if(add[j]>=mod) add[j]-=mod;
pre[j]+=add[j];
if(pre[j]>=mod) pre[j]-=mod;
}
for(int j=1;j<block.size();j++) add[j]=0;
}
cout << (pre[block.size()-1]-1+mod)%mod;
}
Compilation message
boat.cpp: In function 'int main()':
boat.cpp:40:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
40 | for(int i=0;i<v.size();i++)
| ~^~~~~~~~~
boat.cpp:45:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
45 | for(int i=0;i<v.size();i++)
| ~^~~~~~~~~
boat.cpp:50:18: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
50 | for(int i=0;i<block.size();i++) pre[i]=1;
| ~^~~~~~~~~~~~~
boat.cpp:73:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
73 | for(int j=1;j<block.size();j++)
| ~^~~~~~~~~~~~~
boat.cpp:80:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
80 | for(int j=1;j<block.size();j++) add[j]=0;
| ~^~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
2388 KB |
Output is correct |
2 |
Correct |
3 ms |
2388 KB |
Output is correct |
3 |
Correct |
4 ms |
2388 KB |
Output is correct |
4 |
Correct |
3 ms |
2388 KB |
Output is correct |
5 |
Correct |
3 ms |
2388 KB |
Output is correct |
6 |
Correct |
3 ms |
2388 KB |
Output is correct |
7 |
Correct |
4 ms |
2388 KB |
Output is correct |
8 |
Correct |
3 ms |
2388 KB |
Output is correct |
9 |
Correct |
3 ms |
2388 KB |
Output is correct |
10 |
Correct |
3 ms |
2388 KB |
Output is correct |
11 |
Correct |
3 ms |
2388 KB |
Output is correct |
12 |
Correct |
3 ms |
2388 KB |
Output is correct |
13 |
Correct |
3 ms |
2388 KB |
Output is correct |
14 |
Correct |
3 ms |
2388 KB |
Output is correct |
15 |
Correct |
3 ms |
2388 KB |
Output is correct |
16 |
Correct |
1 ms |
724 KB |
Output is correct |
17 |
Correct |
1 ms |
724 KB |
Output is correct |
18 |
Correct |
1 ms |
724 KB |
Output is correct |
19 |
Correct |
1 ms |
724 KB |
Output is correct |
20 |
Correct |
1 ms |
724 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
2388 KB |
Output is correct |
2 |
Correct |
3 ms |
2388 KB |
Output is correct |
3 |
Correct |
4 ms |
2388 KB |
Output is correct |
4 |
Correct |
3 ms |
2388 KB |
Output is correct |
5 |
Correct |
3 ms |
2388 KB |
Output is correct |
6 |
Correct |
3 ms |
2388 KB |
Output is correct |
7 |
Correct |
4 ms |
2388 KB |
Output is correct |
8 |
Correct |
3 ms |
2388 KB |
Output is correct |
9 |
Correct |
3 ms |
2388 KB |
Output is correct |
10 |
Correct |
3 ms |
2388 KB |
Output is correct |
11 |
Correct |
3 ms |
2388 KB |
Output is correct |
12 |
Correct |
3 ms |
2388 KB |
Output is correct |
13 |
Correct |
3 ms |
2388 KB |
Output is correct |
14 |
Correct |
3 ms |
2388 KB |
Output is correct |
15 |
Correct |
3 ms |
2388 KB |
Output is correct |
16 |
Correct |
1 ms |
724 KB |
Output is correct |
17 |
Correct |
1 ms |
724 KB |
Output is correct |
18 |
Correct |
1 ms |
724 KB |
Output is correct |
19 |
Correct |
1 ms |
724 KB |
Output is correct |
20 |
Correct |
1 ms |
724 KB |
Output is correct |
21 |
Correct |
170 ms |
5304 KB |
Output is correct |
22 |
Correct |
151 ms |
5200 KB |
Output is correct |
23 |
Correct |
138 ms |
5052 KB |
Output is correct |
24 |
Correct |
148 ms |
5184 KB |
Output is correct |
25 |
Correct |
172 ms |
5144 KB |
Output is correct |
26 |
Correct |
333 ms |
5720 KB |
Output is correct |
27 |
Correct |
344 ms |
5784 KB |
Output is correct |
28 |
Correct |
362 ms |
5592 KB |
Output is correct |
29 |
Correct |
359 ms |
5620 KB |
Output is correct |
30 |
Correct |
4 ms |
4308 KB |
Output is correct |
31 |
Correct |
5 ms |
4380 KB |
Output is correct |
32 |
Correct |
5 ms |
4308 KB |
Output is correct |
33 |
Correct |
5 ms |
4436 KB |
Output is correct |
34 |
Correct |
3 ms |
4308 KB |
Output is correct |
35 |
Correct |
3 ms |
4436 KB |
Output is correct |
36 |
Correct |
4 ms |
4436 KB |
Output is correct |
37 |
Correct |
4 ms |
4376 KB |
Output is correct |
38 |
Correct |
4 ms |
4436 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
1108 KB |
Output is correct |
2 |
Correct |
2 ms |
1108 KB |
Output is correct |
3 |
Correct |
3 ms |
1108 KB |
Output is correct |
4 |
Correct |
4 ms |
1108 KB |
Output is correct |
5 |
Correct |
3 ms |
1108 KB |
Output is correct |
6 |
Correct |
7 ms |
1132 KB |
Output is correct |
7 |
Correct |
5 ms |
1236 KB |
Output is correct |
8 |
Correct |
5 ms |
1236 KB |
Output is correct |
9 |
Correct |
5 ms |
1224 KB |
Output is correct |
10 |
Correct |
5 ms |
1108 KB |
Output is correct |
11 |
Correct |
3 ms |
1108 KB |
Output is correct |
12 |
Correct |
2 ms |
1108 KB |
Output is correct |
13 |
Correct |
3 ms |
1108 KB |
Output is correct |
14 |
Correct |
3 ms |
1108 KB |
Output is correct |
15 |
Correct |
3 ms |
1108 KB |
Output is correct |
16 |
Correct |
2 ms |
844 KB |
Output is correct |
17 |
Correct |
2 ms |
724 KB |
Output is correct |
18 |
Correct |
2 ms |
864 KB |
Output is correct |
19 |
Correct |
3 ms |
852 KB |
Output is correct |
20 |
Correct |
2 ms |
712 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
2388 KB |
Output is correct |
2 |
Correct |
3 ms |
2388 KB |
Output is correct |
3 |
Correct |
4 ms |
2388 KB |
Output is correct |
4 |
Correct |
3 ms |
2388 KB |
Output is correct |
5 |
Correct |
3 ms |
2388 KB |
Output is correct |
6 |
Correct |
3 ms |
2388 KB |
Output is correct |
7 |
Correct |
4 ms |
2388 KB |
Output is correct |
8 |
Correct |
3 ms |
2388 KB |
Output is correct |
9 |
Correct |
3 ms |
2388 KB |
Output is correct |
10 |
Correct |
3 ms |
2388 KB |
Output is correct |
11 |
Correct |
3 ms |
2388 KB |
Output is correct |
12 |
Correct |
3 ms |
2388 KB |
Output is correct |
13 |
Correct |
3 ms |
2388 KB |
Output is correct |
14 |
Correct |
3 ms |
2388 KB |
Output is correct |
15 |
Correct |
3 ms |
2388 KB |
Output is correct |
16 |
Correct |
1 ms |
724 KB |
Output is correct |
17 |
Correct |
1 ms |
724 KB |
Output is correct |
18 |
Correct |
1 ms |
724 KB |
Output is correct |
19 |
Correct |
1 ms |
724 KB |
Output is correct |
20 |
Correct |
1 ms |
724 KB |
Output is correct |
21 |
Correct |
170 ms |
5304 KB |
Output is correct |
22 |
Correct |
151 ms |
5200 KB |
Output is correct |
23 |
Correct |
138 ms |
5052 KB |
Output is correct |
24 |
Correct |
148 ms |
5184 KB |
Output is correct |
25 |
Correct |
172 ms |
5144 KB |
Output is correct |
26 |
Correct |
333 ms |
5720 KB |
Output is correct |
27 |
Correct |
344 ms |
5784 KB |
Output is correct |
28 |
Correct |
362 ms |
5592 KB |
Output is correct |
29 |
Correct |
359 ms |
5620 KB |
Output is correct |
30 |
Correct |
4 ms |
4308 KB |
Output is correct |
31 |
Correct |
5 ms |
4380 KB |
Output is correct |
32 |
Correct |
5 ms |
4308 KB |
Output is correct |
33 |
Correct |
5 ms |
4436 KB |
Output is correct |
34 |
Correct |
3 ms |
4308 KB |
Output is correct |
35 |
Correct |
3 ms |
4436 KB |
Output is correct |
36 |
Correct |
4 ms |
4436 KB |
Output is correct |
37 |
Correct |
4 ms |
4376 KB |
Output is correct |
38 |
Correct |
4 ms |
4436 KB |
Output is correct |
39 |
Correct |
2 ms |
1108 KB |
Output is correct |
40 |
Correct |
2 ms |
1108 KB |
Output is correct |
41 |
Correct |
3 ms |
1108 KB |
Output is correct |
42 |
Correct |
4 ms |
1108 KB |
Output is correct |
43 |
Correct |
3 ms |
1108 KB |
Output is correct |
44 |
Correct |
7 ms |
1132 KB |
Output is correct |
45 |
Correct |
5 ms |
1236 KB |
Output is correct |
46 |
Correct |
5 ms |
1236 KB |
Output is correct |
47 |
Correct |
5 ms |
1224 KB |
Output is correct |
48 |
Correct |
5 ms |
1108 KB |
Output is correct |
49 |
Correct |
3 ms |
1108 KB |
Output is correct |
50 |
Correct |
2 ms |
1108 KB |
Output is correct |
51 |
Correct |
3 ms |
1108 KB |
Output is correct |
52 |
Correct |
3 ms |
1108 KB |
Output is correct |
53 |
Correct |
3 ms |
1108 KB |
Output is correct |
54 |
Correct |
2 ms |
844 KB |
Output is correct |
55 |
Correct |
2 ms |
724 KB |
Output is correct |
56 |
Correct |
2 ms |
864 KB |
Output is correct |
57 |
Correct |
3 ms |
852 KB |
Output is correct |
58 |
Correct |
2 ms |
712 KB |
Output is correct |
59 |
Correct |
199 ms |
5672 KB |
Output is correct |
60 |
Correct |
173 ms |
5584 KB |
Output is correct |
61 |
Correct |
174 ms |
5692 KB |
Output is correct |
62 |
Correct |
203 ms |
5680 KB |
Output is correct |
63 |
Correct |
179 ms |
5708 KB |
Output is correct |
64 |
Correct |
448 ms |
6352 KB |
Output is correct |
65 |
Correct |
445 ms |
6332 KB |
Output is correct |
66 |
Correct |
446 ms |
6276 KB |
Output is correct |
67 |
Correct |
458 ms |
6356 KB |
Output is correct |
68 |
Correct |
460 ms |
6300 KB |
Output is correct |
69 |
Correct |
157 ms |
5708 KB |
Output is correct |
70 |
Correct |
162 ms |
5556 KB |
Output is correct |
71 |
Correct |
167 ms |
5576 KB |
Output is correct |
72 |
Correct |
171 ms |
5572 KB |
Output is correct |
73 |
Correct |
172 ms |
5708 KB |
Output is correct |
74 |
Correct |
30 ms |
1336 KB |
Output is correct |
75 |
Correct |
29 ms |
1256 KB |
Output is correct |
76 |
Correct |
29 ms |
1276 KB |
Output is correct |
77 |
Correct |
31 ms |
1280 KB |
Output is correct |
78 |
Correct |
34 ms |
1344 KB |
Output is correct |