#include <bits/stdc++.h>
using namespace std;
const int N = 500 + 10,
M = 1'000'000'007;
int n;
int a[N], b[N];
int f[1'010][N];
void add(auto& x, const auto& y) {
x += y;
if (x >= M) x -= M;
}
int powder(int a, int b) {
int ret = 1;
while (b) {
if (b & 1) ret = 1ll * ret * a % M;
a = 1ll * a * a % M;
b >>= 1;
}
return ret;
}
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n;
for (int i = 1; i <= n; ++i) cin >> a[i] >> b[i];
vector<int> rrh(a + 1, a + n + 1);
for (int i = 1; i <= n; ++i) rrh.push_back(b[i] + 1);
sort(rrh.begin(), rrh.end());
rrh.resize(unique(rrh.begin(), rrh.end()) - rrh.begin());
for (int i = 0; i < rrh.size(); ++i) f[i][0] = 1;
for (int i = 1; i < rrh.size(); ++i) {
for (int j = 1; j <= n; ++j) {
auto& ret = f[i][j];
ret = f[i - 1][j];
if (a[j] > rrh[i - 1] || rrh[i - 1] > b[j]) continue;
int len = rrh[i] - rrh[i - 1];
int mul = len, cnt = 1;
for (int t = j - 1; t >= 0; --t) {
add(ret, 1ll * f[i - 1][t] * mul % M);
if (a[t] <= rrh[i - 1] && rrh[i - 1] <= b[t]) {
mul = 1ll * mul * (len + cnt) % M * powder(cnt + 1, M - 2) % M;
cnt += 1;
}
}
}
}
int answer = 0;
for (int i = 1; i <= n; ++i) add(answer, f[rrh.size() - 1][i]);
cout << answer << "\n";
}
Compilation message
boat.cpp:11:10: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
11 | void add(auto& x, const auto& y) {
| ^~~~
boat.cpp:11:25: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
11 | void add(auto& x, const auto& y) {
| ^~~~
boat.cpp: In function 'int32_t main()':
boat.cpp:37:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
37 | for (int i = 0; i < rrh.size(); ++i) f[i][0] = 1;
| ~~^~~~~~~~~~~~
boat.cpp:38:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
38 | for (int i = 1; i < rrh.size(); ++i) {
| ~~^~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2396 KB |
Output is correct |
2 |
Correct |
3 ms |
2396 KB |
Output is correct |
3 |
Correct |
3 ms |
2392 KB |
Output is correct |
4 |
Correct |
3 ms |
2408 KB |
Output is correct |
5 |
Correct |
2 ms |
2396 KB |
Output is correct |
6 |
Correct |
2 ms |
2396 KB |
Output is correct |
7 |
Correct |
2 ms |
2396 KB |
Output is correct |
8 |
Correct |
3 ms |
2392 KB |
Output is correct |
9 |
Correct |
2 ms |
2396 KB |
Output is correct |
10 |
Correct |
3 ms |
2392 KB |
Output is correct |
11 |
Correct |
2 ms |
2396 KB |
Output is correct |
12 |
Correct |
2 ms |
2396 KB |
Output is correct |
13 |
Correct |
3 ms |
2396 KB |
Output is correct |
14 |
Correct |
3 ms |
2396 KB |
Output is correct |
15 |
Correct |
2 ms |
2472 KB |
Output is correct |
16 |
Correct |
2 ms |
604 KB |
Output is correct |
17 |
Correct |
2 ms |
604 KB |
Output is correct |
18 |
Correct |
1 ms |
604 KB |
Output is correct |
19 |
Correct |
2 ms |
728 KB |
Output is correct |
20 |
Correct |
2 ms |
604 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2396 KB |
Output is correct |
2 |
Correct |
3 ms |
2396 KB |
Output is correct |
3 |
Correct |
3 ms |
2392 KB |
Output is correct |
4 |
Correct |
3 ms |
2408 KB |
Output is correct |
5 |
Correct |
2 ms |
2396 KB |
Output is correct |
6 |
Correct |
2 ms |
2396 KB |
Output is correct |
7 |
Correct |
2 ms |
2396 KB |
Output is correct |
8 |
Correct |
3 ms |
2392 KB |
Output is correct |
9 |
Correct |
2 ms |
2396 KB |
Output is correct |
10 |
Correct |
3 ms |
2392 KB |
Output is correct |
11 |
Correct |
2 ms |
2396 KB |
Output is correct |
12 |
Correct |
2 ms |
2396 KB |
Output is correct |
13 |
Correct |
3 ms |
2396 KB |
Output is correct |
14 |
Correct |
3 ms |
2396 KB |
Output is correct |
15 |
Correct |
2 ms |
2472 KB |
Output is correct |
16 |
Correct |
2 ms |
604 KB |
Output is correct |
17 |
Correct |
2 ms |
604 KB |
Output is correct |
18 |
Correct |
1 ms |
604 KB |
Output is correct |
19 |
Correct |
2 ms |
728 KB |
Output is correct |
20 |
Correct |
2 ms |
604 KB |
Output is correct |
21 |
Execution timed out |
2054 ms |
2140 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
21 ms |
860 KB |
Output is correct |
2 |
Correct |
14 ms |
860 KB |
Output is correct |
3 |
Correct |
19 ms |
860 KB |
Output is correct |
4 |
Correct |
20 ms |
860 KB |
Output is correct |
5 |
Correct |
23 ms |
604 KB |
Output is correct |
6 |
Correct |
48 ms |
856 KB |
Output is correct |
7 |
Correct |
48 ms |
600 KB |
Output is correct |
8 |
Correct |
49 ms |
852 KB |
Output is correct |
9 |
Correct |
47 ms |
600 KB |
Output is correct |
10 |
Correct |
48 ms |
860 KB |
Output is correct |
11 |
Correct |
23 ms |
860 KB |
Output is correct |
12 |
Correct |
15 ms |
860 KB |
Output is correct |
13 |
Correct |
20 ms |
600 KB |
Output is correct |
14 |
Correct |
19 ms |
856 KB |
Output is correct |
15 |
Correct |
22 ms |
860 KB |
Output is correct |
16 |
Correct |
14 ms |
604 KB |
Output is correct |
17 |
Correct |
11 ms |
692 KB |
Output is correct |
18 |
Correct |
12 ms |
692 KB |
Output is correct |
19 |
Correct |
11 ms |
692 KB |
Output is correct |
20 |
Correct |
14 ms |
604 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
2396 KB |
Output is correct |
2 |
Correct |
3 ms |
2396 KB |
Output is correct |
3 |
Correct |
3 ms |
2392 KB |
Output is correct |
4 |
Correct |
3 ms |
2408 KB |
Output is correct |
5 |
Correct |
2 ms |
2396 KB |
Output is correct |
6 |
Correct |
2 ms |
2396 KB |
Output is correct |
7 |
Correct |
2 ms |
2396 KB |
Output is correct |
8 |
Correct |
3 ms |
2392 KB |
Output is correct |
9 |
Correct |
2 ms |
2396 KB |
Output is correct |
10 |
Correct |
3 ms |
2392 KB |
Output is correct |
11 |
Correct |
2 ms |
2396 KB |
Output is correct |
12 |
Correct |
2 ms |
2396 KB |
Output is correct |
13 |
Correct |
3 ms |
2396 KB |
Output is correct |
14 |
Correct |
3 ms |
2396 KB |
Output is correct |
15 |
Correct |
2 ms |
2472 KB |
Output is correct |
16 |
Correct |
2 ms |
604 KB |
Output is correct |
17 |
Correct |
2 ms |
604 KB |
Output is correct |
18 |
Correct |
1 ms |
604 KB |
Output is correct |
19 |
Correct |
2 ms |
728 KB |
Output is correct |
20 |
Correct |
2 ms |
604 KB |
Output is correct |
21 |
Execution timed out |
2054 ms |
2140 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |