#include <iostream>
#include <iomanip>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <cassert>
#include <string>
#include <set>
#include <map>
#include <random>
#include <bitset>
#include <string>
#include <unordered_set>
#include <unordered_map>
#include <deque>
#include <queue>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
using namespace std;
using ll = long long;
using ul = unsigned long long;
using ld = long double;
const int N = 1001;
const ll MOD = 1e9 + 7, M2 = MOD * MOD;
ll a[N], b[N], ps[N][N], c[N][N], cd[N][N], rev[N], cs[N][N], dp[N][N];
ll pw(ll x, ll k) {
ll r = 1;
while (k) {
if (k & 1)
r = r * x % MOD;
k >>= 1;
x = x * x % MOD;
}
return r;
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0);
ll n, d;
cin >> n;
vector<ll> li;
rep(i, n) {
cin >> a[i] >> b[i];
b[i]++;
li.push_back(a[i]);
li.push_back(b[i]);
}
sort(all(li));
li.resize(unique(all(li)) - li.begin());
int m = li.size();
rep(i, n) {
a[i] = lower_bound(all(li), a[i]) - li.begin();
b[i] = lower_bound(all(li), b[i]) - li.begin();
rep(j, m)
ps[j][i + 1] = ps[j][i] + (a[i] <= j && j < b[i]);
}
rep(i, n + 1) {
c[i][0] = 1;
for (int j = 1; j <= i; j++)
c[i][j] = (c[i - 1][j - 1] + c[i - 1][j]) % MOD;
rev[i] = pw(i, MOD - 2);
}
rep(i, m - 1) {
d = li[i + 1] - li[i];
cd[i][1] = d;
for (int j = 1; j < n; j++)
cd[i][j + 1] = cd[i][j] * (d - j) % MOD * rev[j + 1] % MOD;
for (int j = 1; j <= n; j++) {
for (int k = 1; k <= j; k++) {
cs[i][j] += c[j - 1][k - 1] * cd[i][k];
if (cs[i][j] >= M2)
cs[i][j] -= M2;
}
cs[i][j] %= MOD;
}
}
rep(i, n) {
for (int j = a[i]; j < b[i]; j++) {
dp[i + 1][j] = cs[j][ps[j][i + 1]];
if (j)
rep(k, i + 1) {
dp[i + 1][j] += dp[k][j - 1] * cs[j][ps[j][i + 1] - ps[j][k]];
if (dp[i + 1][j] >= M2)
dp[i + 1][j] -= M2;
}
dp[i + 1][j] %= MOD;
}
rep(j, m)
dp[i + 1][j + 1] = (dp[i + 1][j] + dp[i + 1][j + 1]) % MOD;
}
ll ans = 0;
rep(i, n + 1) {
ans = (ans + dp[i][m]) % MOD;
}
cout << ans;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
249 ms |
30840 KB |
Output is correct |
2 |
Correct |
247 ms |
30840 KB |
Output is correct |
3 |
Correct |
246 ms |
30840 KB |
Output is correct |
4 |
Correct |
250 ms |
30840 KB |
Output is correct |
5 |
Correct |
247 ms |
30840 KB |
Output is correct |
6 |
Correct |
246 ms |
30840 KB |
Output is correct |
7 |
Correct |
248 ms |
30968 KB |
Output is correct |
8 |
Correct |
245 ms |
30840 KB |
Output is correct |
9 |
Correct |
244 ms |
30812 KB |
Output is correct |
10 |
Correct |
261 ms |
30876 KB |
Output is correct |
11 |
Correct |
246 ms |
30840 KB |
Output is correct |
12 |
Correct |
248 ms |
30768 KB |
Output is correct |
13 |
Correct |
247 ms |
30840 KB |
Output is correct |
14 |
Correct |
244 ms |
30840 KB |
Output is correct |
15 |
Correct |
247 ms |
30968 KB |
Output is correct |
16 |
Correct |
46 ms |
10232 KB |
Output is correct |
17 |
Correct |
49 ms |
10616 KB |
Output is correct |
18 |
Correct |
51 ms |
10360 KB |
Output is correct |
19 |
Correct |
50 ms |
10616 KB |
Output is correct |
20 |
Correct |
48 ms |
10492 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
249 ms |
30840 KB |
Output is correct |
2 |
Correct |
247 ms |
30840 KB |
Output is correct |
3 |
Correct |
246 ms |
30840 KB |
Output is correct |
4 |
Correct |
250 ms |
30840 KB |
Output is correct |
5 |
Correct |
247 ms |
30840 KB |
Output is correct |
6 |
Correct |
246 ms |
30840 KB |
Output is correct |
7 |
Correct |
248 ms |
30968 KB |
Output is correct |
8 |
Correct |
245 ms |
30840 KB |
Output is correct |
9 |
Correct |
244 ms |
30812 KB |
Output is correct |
10 |
Correct |
261 ms |
30876 KB |
Output is correct |
11 |
Correct |
246 ms |
30840 KB |
Output is correct |
12 |
Correct |
248 ms |
30768 KB |
Output is correct |
13 |
Correct |
247 ms |
30840 KB |
Output is correct |
14 |
Correct |
244 ms |
30840 KB |
Output is correct |
15 |
Correct |
247 ms |
30968 KB |
Output is correct |
16 |
Correct |
46 ms |
10232 KB |
Output is correct |
17 |
Correct |
49 ms |
10616 KB |
Output is correct |
18 |
Correct |
51 ms |
10360 KB |
Output is correct |
19 |
Correct |
50 ms |
10616 KB |
Output is correct |
20 |
Correct |
48 ms |
10492 KB |
Output is correct |
21 |
Correct |
352 ms |
28664 KB |
Output is correct |
22 |
Correct |
354 ms |
29048 KB |
Output is correct |
23 |
Correct |
328 ms |
28664 KB |
Output is correct |
24 |
Correct |
321 ms |
28408 KB |
Output is correct |
25 |
Correct |
329 ms |
28680 KB |
Output is correct |
26 |
Correct |
361 ms |
28024 KB |
Output is correct |
27 |
Correct |
378 ms |
28408 KB |
Output is correct |
28 |
Correct |
364 ms |
27896 KB |
Output is correct |
29 |
Correct |
357 ms |
27896 KB |
Output is correct |
30 |
Correct |
254 ms |
30716 KB |
Output is correct |
31 |
Correct |
246 ms |
30840 KB |
Output is correct |
32 |
Correct |
248 ms |
30972 KB |
Output is correct |
33 |
Correct |
248 ms |
30840 KB |
Output is correct |
34 |
Correct |
243 ms |
30712 KB |
Output is correct |
35 |
Correct |
256 ms |
30712 KB |
Output is correct |
36 |
Correct |
252 ms |
30712 KB |
Output is correct |
37 |
Correct |
253 ms |
30712 KB |
Output is correct |
38 |
Correct |
255 ms |
30712 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
4224 KB |
Output is correct |
2 |
Correct |
6 ms |
4224 KB |
Output is correct |
3 |
Correct |
6 ms |
4224 KB |
Output is correct |
4 |
Correct |
8 ms |
4224 KB |
Output is correct |
5 |
Correct |
7 ms |
4224 KB |
Output is correct |
6 |
Correct |
7 ms |
4224 KB |
Output is correct |
7 |
Correct |
8 ms |
4224 KB |
Output is correct |
8 |
Correct |
7 ms |
4224 KB |
Output is correct |
9 |
Correct |
8 ms |
4224 KB |
Output is correct |
10 |
Correct |
8 ms |
4224 KB |
Output is correct |
11 |
Correct |
6 ms |
4224 KB |
Output is correct |
12 |
Correct |
6 ms |
4224 KB |
Output is correct |
13 |
Correct |
6 ms |
4224 KB |
Output is correct |
14 |
Correct |
6 ms |
4224 KB |
Output is correct |
15 |
Correct |
6 ms |
4224 KB |
Output is correct |
16 |
Correct |
4 ms |
2944 KB |
Output is correct |
17 |
Correct |
4 ms |
2944 KB |
Output is correct |
18 |
Correct |
4 ms |
2944 KB |
Output is correct |
19 |
Correct |
4 ms |
2944 KB |
Output is correct |
20 |
Correct |
4 ms |
2816 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
249 ms |
30840 KB |
Output is correct |
2 |
Correct |
247 ms |
30840 KB |
Output is correct |
3 |
Correct |
246 ms |
30840 KB |
Output is correct |
4 |
Correct |
250 ms |
30840 KB |
Output is correct |
5 |
Correct |
247 ms |
30840 KB |
Output is correct |
6 |
Correct |
246 ms |
30840 KB |
Output is correct |
7 |
Correct |
248 ms |
30968 KB |
Output is correct |
8 |
Correct |
245 ms |
30840 KB |
Output is correct |
9 |
Correct |
244 ms |
30812 KB |
Output is correct |
10 |
Correct |
261 ms |
30876 KB |
Output is correct |
11 |
Correct |
246 ms |
30840 KB |
Output is correct |
12 |
Correct |
248 ms |
30768 KB |
Output is correct |
13 |
Correct |
247 ms |
30840 KB |
Output is correct |
14 |
Correct |
244 ms |
30840 KB |
Output is correct |
15 |
Correct |
247 ms |
30968 KB |
Output is correct |
16 |
Correct |
46 ms |
10232 KB |
Output is correct |
17 |
Correct |
49 ms |
10616 KB |
Output is correct |
18 |
Correct |
51 ms |
10360 KB |
Output is correct |
19 |
Correct |
50 ms |
10616 KB |
Output is correct |
20 |
Correct |
48 ms |
10492 KB |
Output is correct |
21 |
Correct |
352 ms |
28664 KB |
Output is correct |
22 |
Correct |
354 ms |
29048 KB |
Output is correct |
23 |
Correct |
328 ms |
28664 KB |
Output is correct |
24 |
Correct |
321 ms |
28408 KB |
Output is correct |
25 |
Correct |
329 ms |
28680 KB |
Output is correct |
26 |
Correct |
361 ms |
28024 KB |
Output is correct |
27 |
Correct |
378 ms |
28408 KB |
Output is correct |
28 |
Correct |
364 ms |
27896 KB |
Output is correct |
29 |
Correct |
357 ms |
27896 KB |
Output is correct |
30 |
Correct |
254 ms |
30716 KB |
Output is correct |
31 |
Correct |
246 ms |
30840 KB |
Output is correct |
32 |
Correct |
248 ms |
30972 KB |
Output is correct |
33 |
Correct |
248 ms |
30840 KB |
Output is correct |
34 |
Correct |
243 ms |
30712 KB |
Output is correct |
35 |
Correct |
256 ms |
30712 KB |
Output is correct |
36 |
Correct |
252 ms |
30712 KB |
Output is correct |
37 |
Correct |
253 ms |
30712 KB |
Output is correct |
38 |
Correct |
255 ms |
30712 KB |
Output is correct |
39 |
Correct |
6 ms |
4224 KB |
Output is correct |
40 |
Correct |
6 ms |
4224 KB |
Output is correct |
41 |
Correct |
6 ms |
4224 KB |
Output is correct |
42 |
Correct |
8 ms |
4224 KB |
Output is correct |
43 |
Correct |
7 ms |
4224 KB |
Output is correct |
44 |
Correct |
7 ms |
4224 KB |
Output is correct |
45 |
Correct |
8 ms |
4224 KB |
Output is correct |
46 |
Correct |
7 ms |
4224 KB |
Output is correct |
47 |
Correct |
8 ms |
4224 KB |
Output is correct |
48 |
Correct |
8 ms |
4224 KB |
Output is correct |
49 |
Correct |
6 ms |
4224 KB |
Output is correct |
50 |
Correct |
6 ms |
4224 KB |
Output is correct |
51 |
Correct |
6 ms |
4224 KB |
Output is correct |
52 |
Correct |
6 ms |
4224 KB |
Output is correct |
53 |
Correct |
6 ms |
4224 KB |
Output is correct |
54 |
Correct |
4 ms |
2944 KB |
Output is correct |
55 |
Correct |
4 ms |
2944 KB |
Output is correct |
56 |
Correct |
4 ms |
2944 KB |
Output is correct |
57 |
Correct |
4 ms |
2944 KB |
Output is correct |
58 |
Correct |
4 ms |
2816 KB |
Output is correct |
59 |
Correct |
449 ms |
30908 KB |
Output is correct |
60 |
Correct |
433 ms |
30840 KB |
Output is correct |
61 |
Correct |
443 ms |
30964 KB |
Output is correct |
62 |
Correct |
446 ms |
30840 KB |
Output is correct |
63 |
Correct |
435 ms |
30840 KB |
Output is correct |
64 |
Correct |
585 ms |
30848 KB |
Output is correct |
65 |
Correct |
566 ms |
30768 KB |
Output is correct |
66 |
Correct |
600 ms |
30840 KB |
Output is correct |
67 |
Correct |
595 ms |
30840 KB |
Output is correct |
68 |
Correct |
591 ms |
30840 KB |
Output is correct |
69 |
Correct |
419 ms |
30840 KB |
Output is correct |
70 |
Correct |
431 ms |
30824 KB |
Output is correct |
71 |
Correct |
406 ms |
30840 KB |
Output is correct |
72 |
Correct |
435 ms |
30880 KB |
Output is correct |
73 |
Correct |
449 ms |
30840 KB |
Output is correct |
74 |
Correct |
70 ms |
10360 KB |
Output is correct |
75 |
Correct |
71 ms |
10488 KB |
Output is correct |
76 |
Correct |
71 ms |
10360 KB |
Output is correct |
77 |
Correct |
73 ms |
10360 KB |
Output is correct |
78 |
Correct |
72 ms |
10360 KB |
Output is correct |