#include<bits/stdc++.h>
using namespace std;
int mod=1e9+7;
long long mypow(long long m,long long y){
if(y==0){
return 1;
}
long long p=mypow(m,(y>>1));
p*=p;
p%=mod;
if(y&1){
p*=m;
p%=mod;
}
return p;
}
inline int ww(int a){
if(a>=mod){
a-=mod;
}
return a;
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin>>n;
vector<int>rev(n+6);
for(int i=0;i<=n+5;i++){
rev[i]=mypow(i,mod-2);
}
vector<pair<int,int>>all(n+1);
vector<int>allind;
for(int i=1;i<=n;i++){
cin>>all[i].first>>all[i].second;
allind.push_back(all[i].first);
allind.push_back(all[i].second);
allind.push_back(all[i].first-1);
}
allind.push_back(0);
sort(allind.begin(),allind.end());
allind.resize(unique(allind.begin(),allind.end())-allind.begin());
int sz=(int)allind.size()+1;
vector<vector<int>>dp(sz+10,vector<int>(n+5));
vector<long long>ps(sz+10);
dp[0][0]=1;
for(int i=0;i<sz+10;i++){
ps[i]=1;
}
for(int i=1;i<=n;i++){
int l=lower_bound(allind.begin(),allind.end(),all[i].first)-allind.begin();
int r=lower_bound(allind.begin(),allind.end(),all[i].second)-allind.begin();
for(int j=l;j<=r;j++){
int cnt=allind[j]-allind[j-1];
for(int h=n;h>=2;h--){
dp[j][h]+=1ll*dp[j][h-1]*(cnt-(h-1))%mod*rev[h]%mod;
dp[j][h]=ww(dp[j][h]);
}
dp[j][1]+=1ll*ps[j-1]*cnt%mod;
dp[j][1]=ww(dp[j][1]);
}
ps[0]=dp[0][0];
for(int i=1;i<=sz+9;i++){
ps[i]=ps[i-1];
for(int h=0;h<=n;h++){
ps[i]+=dp[i][h];
}
ps[i]%=mod;
}
}
long long res=ps[sz+8];
res+=mod-1;
res%=mod;
cout<<res<<"\n";
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
193 ms |
2260 KB |
Output is correct |
2 |
Correct |
154 ms |
2260 KB |
Output is correct |
3 |
Correct |
153 ms |
2260 KB |
Output is correct |
4 |
Correct |
175 ms |
2260 KB |
Output is correct |
5 |
Correct |
150 ms |
2260 KB |
Output is correct |
6 |
Correct |
170 ms |
2368 KB |
Output is correct |
7 |
Correct |
153 ms |
2260 KB |
Output is correct |
8 |
Correct |
149 ms |
2260 KB |
Output is correct |
9 |
Correct |
162 ms |
2364 KB |
Output is correct |
10 |
Correct |
156 ms |
2356 KB |
Output is correct |
11 |
Correct |
157 ms |
2260 KB |
Output is correct |
12 |
Correct |
172 ms |
2360 KB |
Output is correct |
13 |
Correct |
168 ms |
2364 KB |
Output is correct |
14 |
Correct |
153 ms |
2356 KB |
Output is correct |
15 |
Correct |
149 ms |
2372 KB |
Output is correct |
16 |
Correct |
29 ms |
596 KB |
Output is correct |
17 |
Correct |
34 ms |
724 KB |
Output is correct |
18 |
Correct |
31 ms |
724 KB |
Output is correct |
19 |
Correct |
29 ms |
724 KB |
Output is correct |
20 |
Correct |
35 ms |
596 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
193 ms |
2260 KB |
Output is correct |
2 |
Correct |
154 ms |
2260 KB |
Output is correct |
3 |
Correct |
153 ms |
2260 KB |
Output is correct |
4 |
Correct |
175 ms |
2260 KB |
Output is correct |
5 |
Correct |
150 ms |
2260 KB |
Output is correct |
6 |
Correct |
170 ms |
2368 KB |
Output is correct |
7 |
Correct |
153 ms |
2260 KB |
Output is correct |
8 |
Correct |
149 ms |
2260 KB |
Output is correct |
9 |
Correct |
162 ms |
2364 KB |
Output is correct |
10 |
Correct |
156 ms |
2356 KB |
Output is correct |
11 |
Correct |
157 ms |
2260 KB |
Output is correct |
12 |
Correct |
172 ms |
2360 KB |
Output is correct |
13 |
Correct |
168 ms |
2364 KB |
Output is correct |
14 |
Correct |
153 ms |
2356 KB |
Output is correct |
15 |
Correct |
149 ms |
2372 KB |
Output is correct |
16 |
Correct |
29 ms |
596 KB |
Output is correct |
17 |
Correct |
34 ms |
724 KB |
Output is correct |
18 |
Correct |
31 ms |
724 KB |
Output is correct |
19 |
Correct |
29 ms |
724 KB |
Output is correct |
20 |
Correct |
35 ms |
596 KB |
Output is correct |
21 |
Correct |
1248 ms |
2980 KB |
Output is correct |
22 |
Correct |
1246 ms |
3004 KB |
Output is correct |
23 |
Correct |
1224 ms |
2952 KB |
Output is correct |
24 |
Correct |
1262 ms |
3024 KB |
Output is correct |
25 |
Correct |
1218 ms |
2928 KB |
Output is correct |
26 |
Correct |
1622 ms |
2836 KB |
Output is correct |
27 |
Correct |
1611 ms |
2820 KB |
Output is correct |
28 |
Correct |
1635 ms |
2836 KB |
Output is correct |
29 |
Correct |
1727 ms |
2820 KB |
Output is correct |
30 |
Correct |
252 ms |
3260 KB |
Output is correct |
31 |
Correct |
281 ms |
3264 KB |
Output is correct |
32 |
Correct |
234 ms |
3260 KB |
Output is correct |
33 |
Correct |
217 ms |
3260 KB |
Output is correct |
34 |
Correct |
221 ms |
3264 KB |
Output is correct |
35 |
Correct |
158 ms |
2356 KB |
Output is correct |
36 |
Correct |
140 ms |
2356 KB |
Output is correct |
37 |
Correct |
152 ms |
2260 KB |
Output is correct |
38 |
Correct |
148 ms |
2348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
340 KB |
Output is correct |
2 |
Correct |
13 ms |
340 KB |
Output is correct |
3 |
Correct |
12 ms |
464 KB |
Output is correct |
4 |
Correct |
14 ms |
340 KB |
Output is correct |
5 |
Correct |
14 ms |
460 KB |
Output is correct |
6 |
Correct |
19 ms |
456 KB |
Output is correct |
7 |
Correct |
19 ms |
456 KB |
Output is correct |
8 |
Correct |
18 ms |
464 KB |
Output is correct |
9 |
Correct |
19 ms |
464 KB |
Output is correct |
10 |
Correct |
19 ms |
456 KB |
Output is correct |
11 |
Correct |
14 ms |
460 KB |
Output is correct |
12 |
Correct |
12 ms |
340 KB |
Output is correct |
13 |
Correct |
13 ms |
464 KB |
Output is correct |
14 |
Correct |
12 ms |
464 KB |
Output is correct |
15 |
Correct |
14 ms |
340 KB |
Output is correct |
16 |
Correct |
7 ms |
340 KB |
Output is correct |
17 |
Correct |
7 ms |
392 KB |
Output is correct |
18 |
Correct |
7 ms |
340 KB |
Output is correct |
19 |
Correct |
6 ms |
340 KB |
Output is correct |
20 |
Correct |
7 ms |
340 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
193 ms |
2260 KB |
Output is correct |
2 |
Correct |
154 ms |
2260 KB |
Output is correct |
3 |
Correct |
153 ms |
2260 KB |
Output is correct |
4 |
Correct |
175 ms |
2260 KB |
Output is correct |
5 |
Correct |
150 ms |
2260 KB |
Output is correct |
6 |
Correct |
170 ms |
2368 KB |
Output is correct |
7 |
Correct |
153 ms |
2260 KB |
Output is correct |
8 |
Correct |
149 ms |
2260 KB |
Output is correct |
9 |
Correct |
162 ms |
2364 KB |
Output is correct |
10 |
Correct |
156 ms |
2356 KB |
Output is correct |
11 |
Correct |
157 ms |
2260 KB |
Output is correct |
12 |
Correct |
172 ms |
2360 KB |
Output is correct |
13 |
Correct |
168 ms |
2364 KB |
Output is correct |
14 |
Correct |
153 ms |
2356 KB |
Output is correct |
15 |
Correct |
149 ms |
2372 KB |
Output is correct |
16 |
Correct |
29 ms |
596 KB |
Output is correct |
17 |
Correct |
34 ms |
724 KB |
Output is correct |
18 |
Correct |
31 ms |
724 KB |
Output is correct |
19 |
Correct |
29 ms |
724 KB |
Output is correct |
20 |
Correct |
35 ms |
596 KB |
Output is correct |
21 |
Correct |
1248 ms |
2980 KB |
Output is correct |
22 |
Correct |
1246 ms |
3004 KB |
Output is correct |
23 |
Correct |
1224 ms |
2952 KB |
Output is correct |
24 |
Correct |
1262 ms |
3024 KB |
Output is correct |
25 |
Correct |
1218 ms |
2928 KB |
Output is correct |
26 |
Correct |
1622 ms |
2836 KB |
Output is correct |
27 |
Correct |
1611 ms |
2820 KB |
Output is correct |
28 |
Correct |
1635 ms |
2836 KB |
Output is correct |
29 |
Correct |
1727 ms |
2820 KB |
Output is correct |
30 |
Correct |
252 ms |
3260 KB |
Output is correct |
31 |
Correct |
281 ms |
3264 KB |
Output is correct |
32 |
Correct |
234 ms |
3260 KB |
Output is correct |
33 |
Correct |
217 ms |
3260 KB |
Output is correct |
34 |
Correct |
221 ms |
3264 KB |
Output is correct |
35 |
Correct |
158 ms |
2356 KB |
Output is correct |
36 |
Correct |
140 ms |
2356 KB |
Output is correct |
37 |
Correct |
152 ms |
2260 KB |
Output is correct |
38 |
Correct |
148 ms |
2348 KB |
Output is correct |
39 |
Correct |
12 ms |
340 KB |
Output is correct |
40 |
Correct |
13 ms |
340 KB |
Output is correct |
41 |
Correct |
12 ms |
464 KB |
Output is correct |
42 |
Correct |
14 ms |
340 KB |
Output is correct |
43 |
Correct |
14 ms |
460 KB |
Output is correct |
44 |
Correct |
19 ms |
456 KB |
Output is correct |
45 |
Correct |
19 ms |
456 KB |
Output is correct |
46 |
Correct |
18 ms |
464 KB |
Output is correct |
47 |
Correct |
19 ms |
464 KB |
Output is correct |
48 |
Correct |
19 ms |
456 KB |
Output is correct |
49 |
Correct |
14 ms |
460 KB |
Output is correct |
50 |
Correct |
12 ms |
340 KB |
Output is correct |
51 |
Correct |
13 ms |
464 KB |
Output is correct |
52 |
Correct |
12 ms |
464 KB |
Output is correct |
53 |
Correct |
14 ms |
340 KB |
Output is correct |
54 |
Correct |
7 ms |
340 KB |
Output is correct |
55 |
Correct |
7 ms |
392 KB |
Output is correct |
56 |
Correct |
7 ms |
340 KB |
Output is correct |
57 |
Correct |
6 ms |
340 KB |
Output is correct |
58 |
Correct |
7 ms |
340 KB |
Output is correct |
59 |
Correct |
1579 ms |
3364 KB |
Output is correct |
60 |
Correct |
1640 ms |
3368 KB |
Output is correct |
61 |
Correct |
1633 ms |
3368 KB |
Output is correct |
62 |
Correct |
1721 ms |
3380 KB |
Output is correct |
63 |
Correct |
1688 ms |
3376 KB |
Output is correct |
64 |
Execution timed out |
2075 ms |
3284 KB |
Time limit exceeded |
65 |
Halted |
0 ms |
0 KB |
- |