#include <bits/stdc++.h>
using namespace std;
const int mod = 1e9 + 7;
int segs[250001],dp[250001];
int length[1001];
int segl[1001];
int l[501],r[501];
int dp2[1001];
int inv[250001];
vector <int> v2[1001];
int p(int a,int b){
int r = 1;
while(b > 0){
if(b%2 == 1)r = 1ll*r*a%mod;
a = 1ll*a*a%mod;
b/=2;
}
return r;
}
void precalc(){
for(int i = 0;i <= 250000;i++){
inv[i] = p(i,mod - 2);
}
}
int main(){
precalc();
int n,i,cnt = 1,j,cnt2 = 0,ans = 0;
cin>>n;
for(i = 0;i < n;i++){
cin>>l[i]>>r[i];
segl[i*2] = l[i];
segl[i*2+1] = r[i] + 1;
}
sort(segl,segl + 2*n);
for(i = 1;i < 2*n;i++){
if(segl[i] != segl[cnt - 1]){
segl[cnt++] = segl[i];
}
}
for(i = 0;i < n;i++){
for(j = cnt - 1;j >= 0;j--){
if(l[i] <= segl[j] && segl[j] <= r[i]){
segs[cnt2++] = j;
length[j] = segl[j + 1] - segl[j];
}
}
}
segs[cnt2++] = cnt;
length[cnt] = 1;
for(i = 0;i < cnt2;i++){
dp[i] = 1;
for(j = segs[i] - 1;j >= 0;j--){
dp[i]+=dp2[j];
dp[i]%=mod;
}
///update dp2[segs[i]]
dp2[segs[i]] = 0;
v2[segs[i]].push_back(dp[i]);
int prod = length[segs[i]];
for(j = v2[segs[i]].size() - 1;j >= 0;j--){
dp2[segs[i]] = (dp2[segs[i]] + 1ll*v2[segs[i]][j]*prod)%mod;
prod = 1ll*prod*(length[segs[i]] + v2[segs[i]].size() - j)%mod;
prod = 1ll*prod*inv[v2[segs[i]].size() - j + 1]%mod;
}
}
ans = (dp[cnt2 - 1] + mod - 1)%mod;
cout<<ans;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
39 ms |
1236 KB |
Output is correct |
2 |
Correct |
36 ms |
1200 KB |
Output is correct |
3 |
Correct |
36 ms |
1280 KB |
Output is correct |
4 |
Correct |
36 ms |
1236 KB |
Output is correct |
5 |
Correct |
36 ms |
1228 KB |
Output is correct |
6 |
Correct |
38 ms |
1228 KB |
Output is correct |
7 |
Correct |
39 ms |
1240 KB |
Output is correct |
8 |
Correct |
38 ms |
1260 KB |
Output is correct |
9 |
Correct |
36 ms |
1208 KB |
Output is correct |
10 |
Correct |
37 ms |
1228 KB |
Output is correct |
11 |
Correct |
36 ms |
1256 KB |
Output is correct |
12 |
Correct |
36 ms |
1200 KB |
Output is correct |
13 |
Correct |
36 ms |
1236 KB |
Output is correct |
14 |
Correct |
37 ms |
1324 KB |
Output is correct |
15 |
Correct |
37 ms |
1208 KB |
Output is correct |
16 |
Correct |
38 ms |
1232 KB |
Output is correct |
17 |
Correct |
38 ms |
1228 KB |
Output is correct |
18 |
Correct |
36 ms |
1208 KB |
Output is correct |
19 |
Correct |
35 ms |
1292 KB |
Output is correct |
20 |
Correct |
36 ms |
1312 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
39 ms |
1236 KB |
Output is correct |
2 |
Correct |
36 ms |
1200 KB |
Output is correct |
3 |
Correct |
36 ms |
1280 KB |
Output is correct |
4 |
Correct |
36 ms |
1236 KB |
Output is correct |
5 |
Correct |
36 ms |
1228 KB |
Output is correct |
6 |
Correct |
38 ms |
1228 KB |
Output is correct |
7 |
Correct |
39 ms |
1240 KB |
Output is correct |
8 |
Correct |
38 ms |
1260 KB |
Output is correct |
9 |
Correct |
36 ms |
1208 KB |
Output is correct |
10 |
Correct |
37 ms |
1228 KB |
Output is correct |
11 |
Correct |
36 ms |
1256 KB |
Output is correct |
12 |
Correct |
36 ms |
1200 KB |
Output is correct |
13 |
Correct |
36 ms |
1236 KB |
Output is correct |
14 |
Correct |
37 ms |
1324 KB |
Output is correct |
15 |
Correct |
37 ms |
1208 KB |
Output is correct |
16 |
Correct |
38 ms |
1232 KB |
Output is correct |
17 |
Correct |
38 ms |
1228 KB |
Output is correct |
18 |
Correct |
36 ms |
1208 KB |
Output is correct |
19 |
Correct |
35 ms |
1292 KB |
Output is correct |
20 |
Correct |
36 ms |
1312 KB |
Output is correct |
21 |
Correct |
477 ms |
3364 KB |
Output is correct |
22 |
Correct |
455 ms |
3380 KB |
Output is correct |
23 |
Correct |
414 ms |
3320 KB |
Output is correct |
24 |
Correct |
445 ms |
3352 KB |
Output is correct |
25 |
Correct |
472 ms |
3404 KB |
Output is correct |
26 |
Correct |
767 ms |
4260 KB |
Output is correct |
27 |
Correct |
780 ms |
4252 KB |
Output is correct |
28 |
Correct |
761 ms |
4176 KB |
Output is correct |
29 |
Correct |
747 ms |
4168 KB |
Output is correct |
30 |
Correct |
37 ms |
1244 KB |
Output is correct |
31 |
Correct |
38 ms |
1284 KB |
Output is correct |
32 |
Correct |
41 ms |
1356 KB |
Output is correct |
33 |
Correct |
39 ms |
1292 KB |
Output is correct |
34 |
Correct |
38 ms |
1256 KB |
Output is correct |
35 |
Correct |
38 ms |
1352 KB |
Output is correct |
36 |
Correct |
38 ms |
1360 KB |
Output is correct |
37 |
Correct |
38 ms |
1256 KB |
Output is correct |
38 |
Correct |
41 ms |
1356 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
44 ms |
1396 KB |
Output is correct |
2 |
Correct |
38 ms |
1300 KB |
Output is correct |
3 |
Correct |
43 ms |
1384 KB |
Output is correct |
4 |
Correct |
39 ms |
1408 KB |
Output is correct |
5 |
Correct |
40 ms |
1356 KB |
Output is correct |
6 |
Correct |
42 ms |
1384 KB |
Output is correct |
7 |
Correct |
45 ms |
1504 KB |
Output is correct |
8 |
Correct |
41 ms |
1356 KB |
Output is correct |
9 |
Correct |
41 ms |
1372 KB |
Output is correct |
10 |
Correct |
41 ms |
1416 KB |
Output is correct |
11 |
Correct |
40 ms |
1420 KB |
Output is correct |
12 |
Correct |
38 ms |
1356 KB |
Output is correct |
13 |
Correct |
40 ms |
1372 KB |
Output is correct |
14 |
Correct |
41 ms |
1360 KB |
Output is correct |
15 |
Correct |
39 ms |
1308 KB |
Output is correct |
16 |
Correct |
37 ms |
1356 KB |
Output is correct |
17 |
Correct |
38 ms |
1260 KB |
Output is correct |
18 |
Correct |
38 ms |
1304 KB |
Output is correct |
19 |
Correct |
37 ms |
1372 KB |
Output is correct |
20 |
Correct |
37 ms |
1356 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
39 ms |
1236 KB |
Output is correct |
2 |
Correct |
36 ms |
1200 KB |
Output is correct |
3 |
Correct |
36 ms |
1280 KB |
Output is correct |
4 |
Correct |
36 ms |
1236 KB |
Output is correct |
5 |
Correct |
36 ms |
1228 KB |
Output is correct |
6 |
Correct |
38 ms |
1228 KB |
Output is correct |
7 |
Correct |
39 ms |
1240 KB |
Output is correct |
8 |
Correct |
38 ms |
1260 KB |
Output is correct |
9 |
Correct |
36 ms |
1208 KB |
Output is correct |
10 |
Correct |
37 ms |
1228 KB |
Output is correct |
11 |
Correct |
36 ms |
1256 KB |
Output is correct |
12 |
Correct |
36 ms |
1200 KB |
Output is correct |
13 |
Correct |
36 ms |
1236 KB |
Output is correct |
14 |
Correct |
37 ms |
1324 KB |
Output is correct |
15 |
Correct |
37 ms |
1208 KB |
Output is correct |
16 |
Correct |
38 ms |
1232 KB |
Output is correct |
17 |
Correct |
38 ms |
1228 KB |
Output is correct |
18 |
Correct |
36 ms |
1208 KB |
Output is correct |
19 |
Correct |
35 ms |
1292 KB |
Output is correct |
20 |
Correct |
36 ms |
1312 KB |
Output is correct |
21 |
Correct |
477 ms |
3364 KB |
Output is correct |
22 |
Correct |
455 ms |
3380 KB |
Output is correct |
23 |
Correct |
414 ms |
3320 KB |
Output is correct |
24 |
Correct |
445 ms |
3352 KB |
Output is correct |
25 |
Correct |
472 ms |
3404 KB |
Output is correct |
26 |
Correct |
767 ms |
4260 KB |
Output is correct |
27 |
Correct |
780 ms |
4252 KB |
Output is correct |
28 |
Correct |
761 ms |
4176 KB |
Output is correct |
29 |
Correct |
747 ms |
4168 KB |
Output is correct |
30 |
Correct |
37 ms |
1244 KB |
Output is correct |
31 |
Correct |
38 ms |
1284 KB |
Output is correct |
32 |
Correct |
41 ms |
1356 KB |
Output is correct |
33 |
Correct |
39 ms |
1292 KB |
Output is correct |
34 |
Correct |
38 ms |
1256 KB |
Output is correct |
35 |
Correct |
38 ms |
1352 KB |
Output is correct |
36 |
Correct |
38 ms |
1360 KB |
Output is correct |
37 |
Correct |
38 ms |
1256 KB |
Output is correct |
38 |
Correct |
41 ms |
1356 KB |
Output is correct |
39 |
Correct |
44 ms |
1396 KB |
Output is correct |
40 |
Correct |
38 ms |
1300 KB |
Output is correct |
41 |
Correct |
43 ms |
1384 KB |
Output is correct |
42 |
Correct |
39 ms |
1408 KB |
Output is correct |
43 |
Correct |
40 ms |
1356 KB |
Output is correct |
44 |
Correct |
42 ms |
1384 KB |
Output is correct |
45 |
Correct |
45 ms |
1504 KB |
Output is correct |
46 |
Correct |
41 ms |
1356 KB |
Output is correct |
47 |
Correct |
41 ms |
1372 KB |
Output is correct |
48 |
Correct |
41 ms |
1416 KB |
Output is correct |
49 |
Correct |
40 ms |
1420 KB |
Output is correct |
50 |
Correct |
38 ms |
1356 KB |
Output is correct |
51 |
Correct |
40 ms |
1372 KB |
Output is correct |
52 |
Correct |
41 ms |
1360 KB |
Output is correct |
53 |
Correct |
39 ms |
1308 KB |
Output is correct |
54 |
Correct |
37 ms |
1356 KB |
Output is correct |
55 |
Correct |
38 ms |
1260 KB |
Output is correct |
56 |
Correct |
38 ms |
1304 KB |
Output is correct |
57 |
Correct |
37 ms |
1372 KB |
Output is correct |
58 |
Correct |
37 ms |
1356 KB |
Output is correct |
59 |
Correct |
526 ms |
3568 KB |
Output is correct |
60 |
Correct |
506 ms |
3472 KB |
Output is correct |
61 |
Correct |
467 ms |
3468 KB |
Output is correct |
62 |
Correct |
552 ms |
3864 KB |
Output is correct |
63 |
Correct |
512 ms |
3512 KB |
Output is correct |
64 |
Correct |
900 ms |
4632 KB |
Output is correct |
65 |
Correct |
923 ms |
4588 KB |
Output is correct |
66 |
Correct |
917 ms |
4564 KB |
Output is correct |
67 |
Correct |
918 ms |
4616 KB |
Output is correct |
68 |
Correct |
918 ms |
4584 KB |
Output is correct |
69 |
Correct |
488 ms |
3372 KB |
Output is correct |
70 |
Correct |
467 ms |
3436 KB |
Output is correct |
71 |
Correct |
468 ms |
3616 KB |
Output is correct |
72 |
Correct |
514 ms |
3508 KB |
Output is correct |
73 |
Correct |
509 ms |
3404 KB |
Output is correct |
74 |
Correct |
81 ms |
1756 KB |
Output is correct |
75 |
Correct |
80 ms |
1700 KB |
Output is correct |
76 |
Correct |
82 ms |
1720 KB |
Output is correct |
77 |
Correct |
84 ms |
1748 KB |
Output is correct |
78 |
Correct |
81 ms |
1820 KB |
Output is correct |