#include<bits/stdc++.h>
using namespace std;
const int N=505;
const int mod=1e9+7;
int n,l[N],r[N],dp[N][N*2],sum[N][N*2],igt[N],gt[N],ways[N*2][N];
int Power(int x,int n)
{
if(!n) return 1;
if(n%2) return 1ll*Power(x,n-1)*x%mod;
int tmp=Power(x,n/2);
return 1ll*tmp*tmp%mod;
}
void init()
{
gt[0]=1;
for(int i=1;i<=N-5;i++) gt[i]=1ll*gt[i-1]*i%mod;
igt[N-5]=Power(gt[N-5],mod-2);
for(int i=N-5-1;i>=0;i--) igt[i]=1ll*igt[i+1]*(i+1)%mod;
}
int C(int k,int n)
{
if(k<0||k>n) return 0;
if(n<=500) return 1ll*gt[n]*igt[n-k]%mod*igt[k]%mod;
int res=igt[k];
for(int i=n-k+1;i<=n;i++) res=1ll*res*i%mod;
return res;
}
main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cin>>n;
init();
vector<int>val;
for(int i=1;i<=n;i++)
{
cin>>l[i]>>r[i];
r[i]++;
val.push_back(l[i]);
val.push_back(r[i]);
}
val.push_back(0);
sort(val.begin(),val.end());
val.erase(unique(val.begin(),val.end()),val.end());
for(int i=1;i<=n;i++)
{
l[i]=lower_bound(val.begin(),val.end(),l[i])-val.begin();
r[i]=lower_bound(val.begin(),val.end(),r[i])-val.begin();
}
int sz=val.size()-1;
for(int i=1;i<=sz-1;i++)
{
for(int k=1;k<=n;k++)
{
int cur=C(k,val[i+1]-val[i]);
for(int j=k;j<=n;j++) ways[i][j]=(ways[i][j]+1ll*cur*C(k-1,j-1)%mod)%mod;
}
}
int res=0;
dp[0][0]=1;
for(int j=0;j<=sz-1;j++) sum[0][j]=1;
for(int i=1;i<=n;i++)
{
for(int j=l[i];j<r[i];j++)
{
int cnt=0;
for(int k=i;k>=1;k--)
{
if(val[l[k]]<=val[j]&&val[j+1]<=val[r[k]]);
else cnt++;
dp[i][j]=(dp[i][j]+1ll*sum[k-1][j-1]*ways[j][i-k+1-cnt]%mod)%mod;
}
}
for(int j=1;j<=sz-1;j++)
{
sum[i][j]=(sum[i][j-1]+dp[i][j])%mod;
}
res=(res+sum[i][sz-1])%mod;
}
cout<<res;
}
Compilation message
boat.cpp:33:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
33 | main()
| ^
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1930 ms |
5960 KB |
Output is correct |
2 |
Correct |
1935 ms |
6008 KB |
Output is correct |
3 |
Correct |
1936 ms |
6148 KB |
Output is correct |
4 |
Correct |
1938 ms |
6136 KB |
Output is correct |
5 |
Correct |
1934 ms |
6188 KB |
Output is correct |
6 |
Correct |
1926 ms |
6512 KB |
Output is correct |
7 |
Correct |
1935 ms |
6524 KB |
Output is correct |
8 |
Correct |
1936 ms |
6304 KB |
Output is correct |
9 |
Correct |
1941 ms |
6652 KB |
Output is correct |
10 |
Correct |
1946 ms |
6360 KB |
Output is correct |
11 |
Correct |
1939 ms |
6392 KB |
Output is correct |
12 |
Correct |
1937 ms |
6360 KB |
Output is correct |
13 |
Correct |
1932 ms |
6520 KB |
Output is correct |
14 |
Correct |
1937 ms |
6352 KB |
Output is correct |
15 |
Correct |
1946 ms |
6376 KB |
Output is correct |
16 |
Correct |
347 ms |
4600 KB |
Output is correct |
17 |
Correct |
372 ms |
4728 KB |
Output is correct |
18 |
Correct |
355 ms |
4608 KB |
Output is correct |
19 |
Correct |
369 ms |
4600 KB |
Output is correct |
20 |
Correct |
358 ms |
4600 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1930 ms |
5960 KB |
Output is correct |
2 |
Correct |
1935 ms |
6008 KB |
Output is correct |
3 |
Correct |
1936 ms |
6148 KB |
Output is correct |
4 |
Correct |
1938 ms |
6136 KB |
Output is correct |
5 |
Correct |
1934 ms |
6188 KB |
Output is correct |
6 |
Correct |
1926 ms |
6512 KB |
Output is correct |
7 |
Correct |
1935 ms |
6524 KB |
Output is correct |
8 |
Correct |
1936 ms |
6304 KB |
Output is correct |
9 |
Correct |
1941 ms |
6652 KB |
Output is correct |
10 |
Correct |
1946 ms |
6360 KB |
Output is correct |
11 |
Correct |
1939 ms |
6392 KB |
Output is correct |
12 |
Correct |
1937 ms |
6360 KB |
Output is correct |
13 |
Correct |
1932 ms |
6520 KB |
Output is correct |
14 |
Correct |
1937 ms |
6352 KB |
Output is correct |
15 |
Correct |
1946 ms |
6376 KB |
Output is correct |
16 |
Correct |
347 ms |
4600 KB |
Output is correct |
17 |
Correct |
372 ms |
4728 KB |
Output is correct |
18 |
Correct |
355 ms |
4608 KB |
Output is correct |
19 |
Correct |
369 ms |
4600 KB |
Output is correct |
20 |
Correct |
358 ms |
4600 KB |
Output is correct |
21 |
Correct |
1753 ms |
6264 KB |
Output is correct |
22 |
Correct |
1747 ms |
6264 KB |
Output is correct |
23 |
Correct |
1704 ms |
6264 KB |
Output is correct |
24 |
Correct |
1717 ms |
6140 KB |
Output is correct |
25 |
Correct |
1725 ms |
6136 KB |
Output is correct |
26 |
Correct |
1803 ms |
6264 KB |
Output is correct |
27 |
Correct |
1802 ms |
6008 KB |
Output is correct |
28 |
Correct |
1779 ms |
6192 KB |
Output is correct |
29 |
Correct |
1768 ms |
6136 KB |
Output is correct |
30 |
Correct |
1874 ms |
6392 KB |
Output is correct |
31 |
Correct |
1875 ms |
6496 KB |
Output is correct |
32 |
Correct |
1872 ms |
6460 KB |
Output is correct |
33 |
Correct |
1870 ms |
6392 KB |
Output is correct |
34 |
Correct |
1904 ms |
6368 KB |
Output is correct |
35 |
Correct |
1871 ms |
6100 KB |
Output is correct |
36 |
Correct |
1885 ms |
6080 KB |
Output is correct |
37 |
Correct |
1932 ms |
6168 KB |
Output is correct |
38 |
Correct |
1882 ms |
6356 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
22 ms |
1528 KB |
Output is correct |
2 |
Correct |
22 ms |
1536 KB |
Output is correct |
3 |
Correct |
22 ms |
1528 KB |
Output is correct |
4 |
Correct |
22 ms |
1536 KB |
Output is correct |
5 |
Correct |
22 ms |
1532 KB |
Output is correct |
6 |
Correct |
23 ms |
1568 KB |
Output is correct |
7 |
Correct |
23 ms |
1536 KB |
Output is correct |
8 |
Correct |
23 ms |
1536 KB |
Output is correct |
9 |
Correct |
24 ms |
1536 KB |
Output is correct |
10 |
Correct |
24 ms |
1536 KB |
Output is correct |
11 |
Correct |
22 ms |
1528 KB |
Output is correct |
12 |
Correct |
21 ms |
1536 KB |
Output is correct |
13 |
Correct |
23 ms |
1536 KB |
Output is correct |
14 |
Correct |
22 ms |
1536 KB |
Output is correct |
15 |
Correct |
22 ms |
1528 KB |
Output is correct |
16 |
Correct |
13 ms |
1408 KB |
Output is correct |
17 |
Correct |
12 ms |
1408 KB |
Output is correct |
18 |
Correct |
12 ms |
1408 KB |
Output is correct |
19 |
Correct |
13 ms |
1408 KB |
Output is correct |
20 |
Correct |
13 ms |
1408 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1930 ms |
5960 KB |
Output is correct |
2 |
Correct |
1935 ms |
6008 KB |
Output is correct |
3 |
Correct |
1936 ms |
6148 KB |
Output is correct |
4 |
Correct |
1938 ms |
6136 KB |
Output is correct |
5 |
Correct |
1934 ms |
6188 KB |
Output is correct |
6 |
Correct |
1926 ms |
6512 KB |
Output is correct |
7 |
Correct |
1935 ms |
6524 KB |
Output is correct |
8 |
Correct |
1936 ms |
6304 KB |
Output is correct |
9 |
Correct |
1941 ms |
6652 KB |
Output is correct |
10 |
Correct |
1946 ms |
6360 KB |
Output is correct |
11 |
Correct |
1939 ms |
6392 KB |
Output is correct |
12 |
Correct |
1937 ms |
6360 KB |
Output is correct |
13 |
Correct |
1932 ms |
6520 KB |
Output is correct |
14 |
Correct |
1937 ms |
6352 KB |
Output is correct |
15 |
Correct |
1946 ms |
6376 KB |
Output is correct |
16 |
Correct |
347 ms |
4600 KB |
Output is correct |
17 |
Correct |
372 ms |
4728 KB |
Output is correct |
18 |
Correct |
355 ms |
4608 KB |
Output is correct |
19 |
Correct |
369 ms |
4600 KB |
Output is correct |
20 |
Correct |
358 ms |
4600 KB |
Output is correct |
21 |
Correct |
1753 ms |
6264 KB |
Output is correct |
22 |
Correct |
1747 ms |
6264 KB |
Output is correct |
23 |
Correct |
1704 ms |
6264 KB |
Output is correct |
24 |
Correct |
1717 ms |
6140 KB |
Output is correct |
25 |
Correct |
1725 ms |
6136 KB |
Output is correct |
26 |
Correct |
1803 ms |
6264 KB |
Output is correct |
27 |
Correct |
1802 ms |
6008 KB |
Output is correct |
28 |
Correct |
1779 ms |
6192 KB |
Output is correct |
29 |
Correct |
1768 ms |
6136 KB |
Output is correct |
30 |
Correct |
1874 ms |
6392 KB |
Output is correct |
31 |
Correct |
1875 ms |
6496 KB |
Output is correct |
32 |
Correct |
1872 ms |
6460 KB |
Output is correct |
33 |
Correct |
1870 ms |
6392 KB |
Output is correct |
34 |
Correct |
1904 ms |
6368 KB |
Output is correct |
35 |
Correct |
1871 ms |
6100 KB |
Output is correct |
36 |
Correct |
1885 ms |
6080 KB |
Output is correct |
37 |
Correct |
1932 ms |
6168 KB |
Output is correct |
38 |
Correct |
1882 ms |
6356 KB |
Output is correct |
39 |
Correct |
22 ms |
1528 KB |
Output is correct |
40 |
Correct |
22 ms |
1536 KB |
Output is correct |
41 |
Correct |
22 ms |
1528 KB |
Output is correct |
42 |
Correct |
22 ms |
1536 KB |
Output is correct |
43 |
Correct |
22 ms |
1532 KB |
Output is correct |
44 |
Correct |
23 ms |
1568 KB |
Output is correct |
45 |
Correct |
23 ms |
1536 KB |
Output is correct |
46 |
Correct |
23 ms |
1536 KB |
Output is correct |
47 |
Correct |
24 ms |
1536 KB |
Output is correct |
48 |
Correct |
24 ms |
1536 KB |
Output is correct |
49 |
Correct |
22 ms |
1528 KB |
Output is correct |
50 |
Correct |
21 ms |
1536 KB |
Output is correct |
51 |
Correct |
23 ms |
1536 KB |
Output is correct |
52 |
Correct |
22 ms |
1536 KB |
Output is correct |
53 |
Correct |
22 ms |
1528 KB |
Output is correct |
54 |
Correct |
13 ms |
1408 KB |
Output is correct |
55 |
Correct |
12 ms |
1408 KB |
Output is correct |
56 |
Correct |
12 ms |
1408 KB |
Output is correct |
57 |
Correct |
13 ms |
1408 KB |
Output is correct |
58 |
Correct |
13 ms |
1408 KB |
Output is correct |
59 |
Execution timed out |
2051 ms |
2316 KB |
Time limit exceeded |
60 |
Halted |
0 ms |
0 KB |
- |