//In the name of God
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const ll maxn = 1024;
const ll mod = 1e9 + 7;
const ll inf = 1e18;
#define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io freopen("input.txt", "r+", stdin);freopen("output.txt", "w+", stdout);
#define pb push_back
#define Mp make_pair
#define F first
#define S second
#define Sz(x) ll((x).size())
#define all(x) (x).begin(), (x).end()
ll pw(ll a, ll b){
ll c = 1;
while(b){
if(b & 1) c = c * a % mod;
a = a * a % mod;
b >>= 1;
}
return c;
}
int n, a[maxn], b[maxn];
ll pre[maxn][maxn];
vector<int> vec;
vector<pll> g[maxn];
int main(){
fast_io;
cin >> n;
for(int i = 1; i <= n; i++){
cin >> a[i] >> b[i];
b[i]++;
vec.pb(a[i]);
vec.pb(b[i]);
}
vec.pb(0);
sort(all(vec));
vec.resize(unique(all(vec)) - vec.begin());
for(int i = 0; i + 1 < Sz(vec); i++){
g[i].pb({0, 0});
int x = vec[i + 1] - vec[i] - 1;
pre[i][0] = 1;
for(int j = 1; j < maxn; j++){
pre[i][j] = pre[i][j - 1] * (x + j) % mod * pw(j, mod - 2) % mod;
}
}
g[0].pb({1, 1});
for(int i = 1; i <= n; i++){
ll x = 0;
for(int j = 0; j < Sz(vec) - 1; j++){
if(vec[j] < a[i] || b[i] <= vec[j]){
x = (x + g[j].back().S) % mod;
continue;
}
ll y = x * pre[j][1] % mod;
for(int k = 0; k < Sz(g[j]); k++){
y = (y + g[j][Sz(g[j]) - 1 - k].F * pre[j][k + 2]) % mod;
}
ll x2 = (x + g[j].back().S) % mod;
g[j].pb(Mp(x, y));
x = x2;
}
}
int ans = 0;
for(int i = 0; i < Sz(vec) - 1; i++){
ans += g[i].back().S;
if(ans >= mod) ans -= mod;
}
cout << (ans - 1 + mod) % mod << "\n";
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
142 ms |
8364 KB |
Output is correct |
2 |
Correct |
149 ms |
8424 KB |
Output is correct |
3 |
Correct |
141 ms |
8336 KB |
Output is correct |
4 |
Correct |
145 ms |
8392 KB |
Output is correct |
5 |
Correct |
143 ms |
8304 KB |
Output is correct |
6 |
Correct |
147 ms |
8596 KB |
Output is correct |
7 |
Correct |
143 ms |
8400 KB |
Output is correct |
8 |
Correct |
150 ms |
8316 KB |
Output is correct |
9 |
Correct |
142 ms |
8356 KB |
Output is correct |
10 |
Correct |
152 ms |
8488 KB |
Output is correct |
11 |
Correct |
143 ms |
8396 KB |
Output is correct |
12 |
Correct |
146 ms |
8304 KB |
Output is correct |
13 |
Correct |
146 ms |
8408 KB |
Output is correct |
14 |
Correct |
146 ms |
8368 KB |
Output is correct |
15 |
Correct |
145 ms |
8384 KB |
Output is correct |
16 |
Correct |
26 ms |
1700 KB |
Output is correct |
17 |
Correct |
27 ms |
1840 KB |
Output is correct |
18 |
Correct |
27 ms |
1804 KB |
Output is correct |
19 |
Correct |
27 ms |
1876 KB |
Output is correct |
20 |
Correct |
27 ms |
1748 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
142 ms |
8364 KB |
Output is correct |
2 |
Correct |
149 ms |
8424 KB |
Output is correct |
3 |
Correct |
141 ms |
8336 KB |
Output is correct |
4 |
Correct |
145 ms |
8392 KB |
Output is correct |
5 |
Correct |
143 ms |
8304 KB |
Output is correct |
6 |
Correct |
147 ms |
8596 KB |
Output is correct |
7 |
Correct |
143 ms |
8400 KB |
Output is correct |
8 |
Correct |
150 ms |
8316 KB |
Output is correct |
9 |
Correct |
142 ms |
8356 KB |
Output is correct |
10 |
Correct |
152 ms |
8488 KB |
Output is correct |
11 |
Correct |
143 ms |
8396 KB |
Output is correct |
12 |
Correct |
146 ms |
8304 KB |
Output is correct |
13 |
Correct |
146 ms |
8408 KB |
Output is correct |
14 |
Correct |
146 ms |
8368 KB |
Output is correct |
15 |
Correct |
145 ms |
8384 KB |
Output is correct |
16 |
Correct |
26 ms |
1700 KB |
Output is correct |
17 |
Correct |
27 ms |
1840 KB |
Output is correct |
18 |
Correct |
27 ms |
1804 KB |
Output is correct |
19 |
Correct |
27 ms |
1876 KB |
Output is correct |
20 |
Correct |
27 ms |
1748 KB |
Output is correct |
21 |
Correct |
201 ms |
11220 KB |
Output is correct |
22 |
Correct |
199 ms |
11340 KB |
Output is correct |
23 |
Correct |
190 ms |
10724 KB |
Output is correct |
24 |
Correct |
199 ms |
11060 KB |
Output is correct |
25 |
Correct |
198 ms |
10916 KB |
Output is correct |
26 |
Correct |
281 ms |
12060 KB |
Output is correct |
27 |
Correct |
284 ms |
12236 KB |
Output is correct |
28 |
Correct |
272 ms |
11980 KB |
Output is correct |
29 |
Correct |
275 ms |
11976 KB |
Output is correct |
30 |
Correct |
140 ms |
8412 KB |
Output is correct |
31 |
Correct |
141 ms |
8316 KB |
Output is correct |
32 |
Correct |
143 ms |
8316 KB |
Output is correct |
33 |
Correct |
150 ms |
8552 KB |
Output is correct |
34 |
Correct |
142 ms |
8396 KB |
Output is correct |
35 |
Correct |
142 ms |
8348 KB |
Output is correct |
36 |
Correct |
145 ms |
8396 KB |
Output is correct |
37 |
Correct |
150 ms |
8336 KB |
Output is correct |
38 |
Correct |
142 ms |
8396 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
32 ms |
2040 KB |
Output is correct |
2 |
Correct |
28 ms |
1996 KB |
Output is correct |
3 |
Correct |
30 ms |
2108 KB |
Output is correct |
4 |
Correct |
28 ms |
2132 KB |
Output is correct |
5 |
Correct |
29 ms |
2128 KB |
Output is correct |
6 |
Correct |
32 ms |
2160 KB |
Output is correct |
7 |
Correct |
31 ms |
2152 KB |
Output is correct |
8 |
Correct |
33 ms |
2260 KB |
Output is correct |
9 |
Correct |
30 ms |
2180 KB |
Output is correct |
10 |
Correct |
30 ms |
2168 KB |
Output is correct |
11 |
Correct |
30 ms |
2032 KB |
Output is correct |
12 |
Correct |
30 ms |
2052 KB |
Output is correct |
13 |
Correct |
30 ms |
2116 KB |
Output is correct |
14 |
Correct |
29 ms |
2132 KB |
Output is correct |
15 |
Correct |
29 ms |
1996 KB |
Output is correct |
16 |
Correct |
18 ms |
1364 KB |
Output is correct |
17 |
Correct |
18 ms |
1384 KB |
Output is correct |
18 |
Correct |
17 ms |
1300 KB |
Output is correct |
19 |
Correct |
17 ms |
1376 KB |
Output is correct |
20 |
Correct |
16 ms |
1360 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
142 ms |
8364 KB |
Output is correct |
2 |
Correct |
149 ms |
8424 KB |
Output is correct |
3 |
Correct |
141 ms |
8336 KB |
Output is correct |
4 |
Correct |
145 ms |
8392 KB |
Output is correct |
5 |
Correct |
143 ms |
8304 KB |
Output is correct |
6 |
Correct |
147 ms |
8596 KB |
Output is correct |
7 |
Correct |
143 ms |
8400 KB |
Output is correct |
8 |
Correct |
150 ms |
8316 KB |
Output is correct |
9 |
Correct |
142 ms |
8356 KB |
Output is correct |
10 |
Correct |
152 ms |
8488 KB |
Output is correct |
11 |
Correct |
143 ms |
8396 KB |
Output is correct |
12 |
Correct |
146 ms |
8304 KB |
Output is correct |
13 |
Correct |
146 ms |
8408 KB |
Output is correct |
14 |
Correct |
146 ms |
8368 KB |
Output is correct |
15 |
Correct |
145 ms |
8384 KB |
Output is correct |
16 |
Correct |
26 ms |
1700 KB |
Output is correct |
17 |
Correct |
27 ms |
1840 KB |
Output is correct |
18 |
Correct |
27 ms |
1804 KB |
Output is correct |
19 |
Correct |
27 ms |
1876 KB |
Output is correct |
20 |
Correct |
27 ms |
1748 KB |
Output is correct |
21 |
Correct |
201 ms |
11220 KB |
Output is correct |
22 |
Correct |
199 ms |
11340 KB |
Output is correct |
23 |
Correct |
190 ms |
10724 KB |
Output is correct |
24 |
Correct |
199 ms |
11060 KB |
Output is correct |
25 |
Correct |
198 ms |
10916 KB |
Output is correct |
26 |
Correct |
281 ms |
12060 KB |
Output is correct |
27 |
Correct |
284 ms |
12236 KB |
Output is correct |
28 |
Correct |
272 ms |
11980 KB |
Output is correct |
29 |
Correct |
275 ms |
11976 KB |
Output is correct |
30 |
Correct |
140 ms |
8412 KB |
Output is correct |
31 |
Correct |
141 ms |
8316 KB |
Output is correct |
32 |
Correct |
143 ms |
8316 KB |
Output is correct |
33 |
Correct |
150 ms |
8552 KB |
Output is correct |
34 |
Correct |
142 ms |
8396 KB |
Output is correct |
35 |
Correct |
142 ms |
8348 KB |
Output is correct |
36 |
Correct |
145 ms |
8396 KB |
Output is correct |
37 |
Correct |
150 ms |
8336 KB |
Output is correct |
38 |
Correct |
142 ms |
8396 KB |
Output is correct |
39 |
Correct |
32 ms |
2040 KB |
Output is correct |
40 |
Correct |
28 ms |
1996 KB |
Output is correct |
41 |
Correct |
30 ms |
2108 KB |
Output is correct |
42 |
Correct |
28 ms |
2132 KB |
Output is correct |
43 |
Correct |
29 ms |
2128 KB |
Output is correct |
44 |
Correct |
32 ms |
2160 KB |
Output is correct |
45 |
Correct |
31 ms |
2152 KB |
Output is correct |
46 |
Correct |
33 ms |
2260 KB |
Output is correct |
47 |
Correct |
30 ms |
2180 KB |
Output is correct |
48 |
Correct |
30 ms |
2168 KB |
Output is correct |
49 |
Correct |
30 ms |
2032 KB |
Output is correct |
50 |
Correct |
30 ms |
2052 KB |
Output is correct |
51 |
Correct |
30 ms |
2116 KB |
Output is correct |
52 |
Correct |
29 ms |
2132 KB |
Output is correct |
53 |
Correct |
29 ms |
1996 KB |
Output is correct |
54 |
Correct |
18 ms |
1364 KB |
Output is correct |
55 |
Correct |
18 ms |
1384 KB |
Output is correct |
56 |
Correct |
17 ms |
1300 KB |
Output is correct |
57 |
Correct |
17 ms |
1376 KB |
Output is correct |
58 |
Correct |
16 ms |
1360 KB |
Output is correct |
59 |
Correct |
222 ms |
12184 KB |
Output is correct |
60 |
Correct |
212 ms |
11812 KB |
Output is correct |
61 |
Correct |
216 ms |
11788 KB |
Output is correct |
62 |
Correct |
222 ms |
12748 KB |
Output is correct |
63 |
Correct |
213 ms |
11852 KB |
Output is correct |
64 |
Correct |
326 ms |
13672 KB |
Output is correct |
65 |
Correct |
319 ms |
13608 KB |
Output is correct |
66 |
Correct |
327 ms |
13704 KB |
Output is correct |
67 |
Correct |
317 ms |
13644 KB |
Output is correct |
68 |
Correct |
324 ms |
13700 KB |
Output is correct |
69 |
Correct |
208 ms |
11736 KB |
Output is correct |
70 |
Correct |
210 ms |
11632 KB |
Output is correct |
71 |
Correct |
218 ms |
11720 KB |
Output is correct |
72 |
Correct |
213 ms |
11756 KB |
Output is correct |
73 |
Correct |
212 ms |
11644 KB |
Output is correct |
74 |
Correct |
42 ms |
2636 KB |
Output is correct |
75 |
Correct |
44 ms |
2556 KB |
Output is correct |
76 |
Correct |
42 ms |
2468 KB |
Output is correct |
77 |
Correct |
41 ms |
2576 KB |
Output is correct |
78 |
Correct |
42 ms |
2632 KB |
Output is correct |