#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;
#define ll long long
#define ull unsigned long long
#define all(aaa) aaa.begin(), aaa.end()
#pragma warning(disable : 4996)
const int N = 505, MOD = 1e9 + 7;
int a[N], b[N], dp[N][N * 2], dp2[N][N], c[N][N], c2[N];
int n;
ll bp(ll a, ll p) {
ll r = 1;
while (p > 0) {
if (p & 1)
r = r * a % MOD;
p >>= 1;
a = a * a % MOD;
}
return r;
}
void f(int& a, int b) {
a += b;
if (a >= MOD)
a -= MOD;
}
signed main() {
#ifdef HOME
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(0);
for (int i = 0; i < N; i++) {
c[i][0] = 1;
}
for (int i = 1; i < N; i++) {
for (int j = 1; j < N; j++) {
c[i][j] = (c[i - 1][j] + c[i - 1][j - 1]) % MOD;
}
}
cin >> n;
vector<int> v;
v.push_back(0);
for (int i = 0; i < n; i++) {
cin >> a[i] >> b[i];
v.push_back(a[i]);
v.push_back(b[i] + 1);
}
sort(all(v));
v.erase(unique(all(v)), v.end());
int m = v.size() - 1;
for (int i = 1; i < m; i++) {
ll t = 1;
for (int j = 0; j <= n; j++) {
c2[j] = t;
t = t * (v[i + 1] - v[i] - j) % MOD * bp(j + 1, MOD - 2) % MOD;
}
for (int j = 0; j <= n; j++) {
for (int h = 1; h <= j; h++) {
dp2[i][j] = (dp2[i][j] + c[j - 1][h - 1] * (ll)c2[h]) % MOD;
}
}
}
dp[0][0] = 1;
for (int i = 0; i < n; i++) {
for (int j = 1; j < m; j++) {
f(dp[i][j], dp[i][j - 1]);
int g = 0;
for (int k = i; k < n; k++) {
if (a[k] <= v[j] && b[k] >= v[j + 1] - 1) {
g++;
dp[k + 1][j] = (dp[k + 1][j] + dp[i][j - 1] * (ll)dp2[j][g]) % MOD;
}
}
}
}
int ans = 0;
for (int i = 1; i < m; i++) {
f(ans, dp[n][i]);
}
for (int i = 1; i < n; i++) {
f(ans, dp[i][m - 1]);
}
cout << ans;
//cout << "\n" << slow();
return 0;
}
Compilation message
boat.cpp:42:0: warning: ignoring #pragma warning [-Wunknown-pragmas]
#pragma warning(disable : 4996)
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1014 ms |
4600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1014 ms |
4600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
16 ms |
2176 KB |
Output is correct |
2 |
Correct |
14 ms |
2176 KB |
Output is correct |
3 |
Correct |
15 ms |
2176 KB |
Output is correct |
4 |
Correct |
15 ms |
2176 KB |
Output is correct |
5 |
Correct |
17 ms |
2048 KB |
Output is correct |
6 |
Correct |
19 ms |
2176 KB |
Output is correct |
7 |
Correct |
16 ms |
2176 KB |
Output is correct |
8 |
Correct |
18 ms |
2176 KB |
Output is correct |
9 |
Correct |
15 ms |
2176 KB |
Output is correct |
10 |
Correct |
16 ms |
2176 KB |
Output is correct |
11 |
Correct |
17 ms |
2092 KB |
Output is correct |
12 |
Correct |
16 ms |
2304 KB |
Output is correct |
13 |
Correct |
15 ms |
2176 KB |
Output is correct |
14 |
Correct |
17 ms |
2176 KB |
Output is correct |
15 |
Correct |
17 ms |
2176 KB |
Output is correct |
16 |
Correct |
12 ms |
1920 KB |
Output is correct |
17 |
Correct |
12 ms |
1920 KB |
Output is correct |
18 |
Correct |
11 ms |
1920 KB |
Output is correct |
19 |
Correct |
11 ms |
1920 KB |
Output is correct |
20 |
Correct |
10 ms |
2048 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1014 ms |
4600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |