// Be name khoda //
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) x.begin(), x.end()
#define fi first
#define se second
#define pb push_back
const int maxn5 = 5e2 + 5;
const int maxnb = 1e3 + 10;
const int mod = 1e9 + 7;
int ent[maxn5][maxn5], val[maxnb][maxn5];
int ent2[maxnb][maxn5], szb[maxnb];
int l[maxn5], r[maxn5], ansel[maxn5][maxnb];
int ansbl[maxnb];
vector <int> exx;
inline ll pw(ll a, ll b){
ll ret = 1;
for(; b; b >>= 1, a = a * a % mod)
if(b&1) ret = ret * a % mod;
return ret;
}
int main(){
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int n; cin >> n;
for(int i = 0; i < n; i++){
cin >> l[i] >> r[i]; // (..]
r[i]++;
exx.pb(l[i]);
exx.pb(r[i]);
}
exx.pb(0);
sort(all(exx));
exx.resize(unique(all(exx)) - exx.begin());
for(int i = 0; i < n; i++){
l[i] = lower_bound(all(exx), l[i]) - exx.begin();
r[i] = lower_bound(all(exx), r[i]) - exx.begin();
//cout << "segment " << i << ' ' << l[i] << ' ' << r[i] << endl;
}
for(int i = 1; i < exx.size(); i++){
szb[i] = exx[i] - exx[i - 1];
//cout << "a bl of " << exx[i] << ' ' << exx[i - 1] << ' ' << szb[i + 1] << endl;
}
int blsz = exx.size();
ent[0][0] = 1;
for(int i = 1; i < maxn5; i++){
ent[i][0] = 1;
for(int j = 1; j <= i; j++)
ent[i][j] = (ent[i - 1][j - 1] + ent[i - 1][j]) % mod;
}
for(int i = 1; i < blsz; i++){
ll s = 1, m = 1;
for(int j = 1; j < maxn5 && j <= szb[i]; j++){
s = s * (szb[i] - j + 1) % mod;
m = m * j % mod;
ent2[i][j] = s * pw(m, mod - 2) % mod;
}
}
for(int i = 1; i < blsz; i++) for(int j = 1; j < n; j++){ // bl e i om hast va j nafar davtalab
// val[i][j] = SIGMA z : C(sz[i], z + 1) * C(j, z);
for(int z = 1; z + 1 <= szb[i] && z <= j; z++)
val[i][j] = (val[i][j] + ll(ent2[i][z + 1]) * ent[j][z]) % mod;
//assert(val[i][j] <= 1 || szb[i] > 1);
}
ansbl[0] = 1;
for(int i = 0; i < n; i++){
for(int j = l[i] + 1; j <= r[i]; j++){
for(int k = 0; k < j; k++)
ansel[i][j] = (ansel[i][j] + ansbl[k] * ll(szb[j])) % mod;
//cout << "cur having " << i << ' ' << j << ' ' << ansel[i][j] << endl;
if(i == 0)
continue;
int num = l[i - 1] < j && j <= r[i - 1];
for(int k = i - 2; k >= 0; k--){
//cout << "aha " << i << ' ' << j << ' ' << k << ' ' << num << ' ' << ansel[k][j - 1] << endl;
if(num)
ansel[i][j] = (ansel[i][j] + ll(ansel[k][j - 1]) * val[j][num]) % mod;
//assert(szb[j] == 1);
//cout << "with " << i << ' ' << j << ' ' << k << ' ' << num << ' ' << ' ' << ansel[k][j - 1] << ' ' << val[j][num] << ' ' << ansel[i][j] << endl;
num += l[k] < j && j <= r[k];
}
if(num)
ansel[i][j] = (ansel[i][j] + val[j][num]) % mod;
}
for(int j = l[i] + 1; j < blsz; j++){
ansbl[j] = (ansbl[j] + ansel[i][j]) % mod;
ansel[i][j] = (ansel[i][j - 1] + ansel[i][j]) % mod;
//cout << i << ' ' << j << ' ' << ansel[i][j] << endl;
}
}
ll out = 0;
for(int i = 1; i < blsz; i++)
out += ansbl[i];
cout << out % mod << endl;
}
Compilation message
boat.cpp: In function 'int main()':
boat.cpp:52:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
52 | for(int i = 1; i < exx.size(); i++){
| ~~^~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
307 ms |
7244 KB |
Output is correct |
2 |
Correct |
309 ms |
7264 KB |
Output is correct |
3 |
Correct |
320 ms |
7264 KB |
Output is correct |
4 |
Correct |
317 ms |
7228 KB |
Output is correct |
5 |
Correct |
324 ms |
7348 KB |
Output is correct |
6 |
Correct |
317 ms |
7176 KB |
Output is correct |
7 |
Correct |
314 ms |
7156 KB |
Output is correct |
8 |
Correct |
314 ms |
7140 KB |
Output is correct |
9 |
Correct |
313 ms |
7380 KB |
Output is correct |
10 |
Correct |
311 ms |
7312 KB |
Output is correct |
11 |
Correct |
317 ms |
7176 KB |
Output is correct |
12 |
Correct |
313 ms |
7344 KB |
Output is correct |
13 |
Correct |
313 ms |
7244 KB |
Output is correct |
14 |
Correct |
323 ms |
7260 KB |
Output is correct |
15 |
Correct |
313 ms |
7244 KB |
Output is correct |
16 |
Correct |
58 ms |
3904 KB |
Output is correct |
17 |
Correct |
63 ms |
4052 KB |
Output is correct |
18 |
Correct |
60 ms |
3976 KB |
Output is correct |
19 |
Correct |
65 ms |
4056 KB |
Output is correct |
20 |
Correct |
68 ms |
3924 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
307 ms |
7244 KB |
Output is correct |
2 |
Correct |
309 ms |
7264 KB |
Output is correct |
3 |
Correct |
320 ms |
7264 KB |
Output is correct |
4 |
Correct |
317 ms |
7228 KB |
Output is correct |
5 |
Correct |
324 ms |
7348 KB |
Output is correct |
6 |
Correct |
317 ms |
7176 KB |
Output is correct |
7 |
Correct |
314 ms |
7156 KB |
Output is correct |
8 |
Correct |
314 ms |
7140 KB |
Output is correct |
9 |
Correct |
313 ms |
7380 KB |
Output is correct |
10 |
Correct |
311 ms |
7312 KB |
Output is correct |
11 |
Correct |
317 ms |
7176 KB |
Output is correct |
12 |
Correct |
313 ms |
7344 KB |
Output is correct |
13 |
Correct |
313 ms |
7244 KB |
Output is correct |
14 |
Correct |
323 ms |
7260 KB |
Output is correct |
15 |
Correct |
313 ms |
7244 KB |
Output is correct |
16 |
Correct |
58 ms |
3904 KB |
Output is correct |
17 |
Correct |
63 ms |
4052 KB |
Output is correct |
18 |
Correct |
60 ms |
3976 KB |
Output is correct |
19 |
Correct |
65 ms |
4056 KB |
Output is correct |
20 |
Correct |
68 ms |
3924 KB |
Output is correct |
21 |
Correct |
599 ms |
6912 KB |
Output is correct |
22 |
Correct |
572 ms |
7048 KB |
Output is correct |
23 |
Correct |
559 ms |
6904 KB |
Output is correct |
24 |
Correct |
560 ms |
6860 KB |
Output is correct |
25 |
Correct |
589 ms |
6824 KB |
Output is correct |
26 |
Correct |
817 ms |
6844 KB |
Output is correct |
27 |
Correct |
833 ms |
6884 KB |
Output is correct |
28 |
Correct |
777 ms |
6760 KB |
Output is correct |
29 |
Correct |
783 ms |
6760 KB |
Output is correct |
30 |
Correct |
298 ms |
7132 KB |
Output is correct |
31 |
Correct |
302 ms |
7216 KB |
Output is correct |
32 |
Correct |
299 ms |
7244 KB |
Output is correct |
33 |
Correct |
301 ms |
7236 KB |
Output is correct |
34 |
Correct |
303 ms |
7204 KB |
Output is correct |
35 |
Correct |
295 ms |
7216 KB |
Output is correct |
36 |
Correct |
299 ms |
7236 KB |
Output is correct |
37 |
Correct |
296 ms |
7164 KB |
Output is correct |
38 |
Correct |
299 ms |
7244 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
26 ms |
2448 KB |
Output is correct |
2 |
Correct |
25 ms |
2516 KB |
Output is correct |
3 |
Correct |
24 ms |
2508 KB |
Output is correct |
4 |
Correct |
25 ms |
2508 KB |
Output is correct |
5 |
Correct |
25 ms |
2408 KB |
Output is correct |
6 |
Correct |
27 ms |
2508 KB |
Output is correct |
7 |
Correct |
28 ms |
2516 KB |
Output is correct |
8 |
Correct |
27 ms |
2500 KB |
Output is correct |
9 |
Correct |
29 ms |
2508 KB |
Output is correct |
10 |
Correct |
28 ms |
2464 KB |
Output is correct |
11 |
Correct |
25 ms |
2452 KB |
Output is correct |
12 |
Correct |
24 ms |
2528 KB |
Output is correct |
13 |
Correct |
24 ms |
2524 KB |
Output is correct |
14 |
Correct |
24 ms |
2516 KB |
Output is correct |
15 |
Correct |
27 ms |
2488 KB |
Output is correct |
16 |
Correct |
12 ms |
2132 KB |
Output is correct |
17 |
Correct |
13 ms |
2132 KB |
Output is correct |
18 |
Correct |
12 ms |
2128 KB |
Output is correct |
19 |
Correct |
12 ms |
2152 KB |
Output is correct |
20 |
Correct |
12 ms |
2124 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
307 ms |
7244 KB |
Output is correct |
2 |
Correct |
309 ms |
7264 KB |
Output is correct |
3 |
Correct |
320 ms |
7264 KB |
Output is correct |
4 |
Correct |
317 ms |
7228 KB |
Output is correct |
5 |
Correct |
324 ms |
7348 KB |
Output is correct |
6 |
Correct |
317 ms |
7176 KB |
Output is correct |
7 |
Correct |
314 ms |
7156 KB |
Output is correct |
8 |
Correct |
314 ms |
7140 KB |
Output is correct |
9 |
Correct |
313 ms |
7380 KB |
Output is correct |
10 |
Correct |
311 ms |
7312 KB |
Output is correct |
11 |
Correct |
317 ms |
7176 KB |
Output is correct |
12 |
Correct |
313 ms |
7344 KB |
Output is correct |
13 |
Correct |
313 ms |
7244 KB |
Output is correct |
14 |
Correct |
323 ms |
7260 KB |
Output is correct |
15 |
Correct |
313 ms |
7244 KB |
Output is correct |
16 |
Correct |
58 ms |
3904 KB |
Output is correct |
17 |
Correct |
63 ms |
4052 KB |
Output is correct |
18 |
Correct |
60 ms |
3976 KB |
Output is correct |
19 |
Correct |
65 ms |
4056 KB |
Output is correct |
20 |
Correct |
68 ms |
3924 KB |
Output is correct |
21 |
Correct |
599 ms |
6912 KB |
Output is correct |
22 |
Correct |
572 ms |
7048 KB |
Output is correct |
23 |
Correct |
559 ms |
6904 KB |
Output is correct |
24 |
Correct |
560 ms |
6860 KB |
Output is correct |
25 |
Correct |
589 ms |
6824 KB |
Output is correct |
26 |
Correct |
817 ms |
6844 KB |
Output is correct |
27 |
Correct |
833 ms |
6884 KB |
Output is correct |
28 |
Correct |
777 ms |
6760 KB |
Output is correct |
29 |
Correct |
783 ms |
6760 KB |
Output is correct |
30 |
Correct |
298 ms |
7132 KB |
Output is correct |
31 |
Correct |
302 ms |
7216 KB |
Output is correct |
32 |
Correct |
299 ms |
7244 KB |
Output is correct |
33 |
Correct |
301 ms |
7236 KB |
Output is correct |
34 |
Correct |
303 ms |
7204 KB |
Output is correct |
35 |
Correct |
295 ms |
7216 KB |
Output is correct |
36 |
Correct |
299 ms |
7236 KB |
Output is correct |
37 |
Correct |
296 ms |
7164 KB |
Output is correct |
38 |
Correct |
299 ms |
7244 KB |
Output is correct |
39 |
Correct |
26 ms |
2448 KB |
Output is correct |
40 |
Correct |
25 ms |
2516 KB |
Output is correct |
41 |
Correct |
24 ms |
2508 KB |
Output is correct |
42 |
Correct |
25 ms |
2508 KB |
Output is correct |
43 |
Correct |
25 ms |
2408 KB |
Output is correct |
44 |
Correct |
27 ms |
2508 KB |
Output is correct |
45 |
Correct |
28 ms |
2516 KB |
Output is correct |
46 |
Correct |
27 ms |
2500 KB |
Output is correct |
47 |
Correct |
29 ms |
2508 KB |
Output is correct |
48 |
Correct |
28 ms |
2464 KB |
Output is correct |
49 |
Correct |
25 ms |
2452 KB |
Output is correct |
50 |
Correct |
24 ms |
2528 KB |
Output is correct |
51 |
Correct |
24 ms |
2524 KB |
Output is correct |
52 |
Correct |
24 ms |
2516 KB |
Output is correct |
53 |
Correct |
27 ms |
2488 KB |
Output is correct |
54 |
Correct |
12 ms |
2132 KB |
Output is correct |
55 |
Correct |
13 ms |
2132 KB |
Output is correct |
56 |
Correct |
12 ms |
2128 KB |
Output is correct |
57 |
Correct |
12 ms |
2152 KB |
Output is correct |
58 |
Correct |
12 ms |
2124 KB |
Output is correct |
59 |
Correct |
1268 ms |
7316 KB |
Output is correct |
60 |
Correct |
1264 ms |
7480 KB |
Output is correct |
61 |
Correct |
1201 ms |
7400 KB |
Output is correct |
62 |
Correct |
1284 ms |
7272 KB |
Output is correct |
63 |
Correct |
1255 ms |
7232 KB |
Output is correct |
64 |
Correct |
1565 ms |
7432 KB |
Output is correct |
65 |
Correct |
1571 ms |
7268 KB |
Output is correct |
66 |
Correct |
1577 ms |
7316 KB |
Output is correct |
67 |
Correct |
1574 ms |
7520 KB |
Output is correct |
68 |
Correct |
1547 ms |
7244 KB |
Output is correct |
69 |
Correct |
1184 ms |
7324 KB |
Output is correct |
70 |
Correct |
1177 ms |
7176 KB |
Output is correct |
71 |
Correct |
1161 ms |
7268 KB |
Output is correct |
72 |
Correct |
1182 ms |
7304 KB |
Output is correct |
73 |
Correct |
1190 ms |
7196 KB |
Output is correct |
74 |
Correct |
134 ms |
3912 KB |
Output is correct |
75 |
Correct |
130 ms |
4004 KB |
Output is correct |
76 |
Correct |
133 ms |
3936 KB |
Output is correct |
77 |
Correct |
136 ms |
4044 KB |
Output is correct |
78 |
Correct |
136 ms |
4000 KB |
Output is correct |