#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
#define int long long
#define vel vector<long long>
#define V vector
#define ll long long
#define rep(i,n) for(int i=0;i<n;i++)
int pr = 1000000007;
int ref(int &a) {
a = a % pr;
a += pr;
a = a % pr;
return a;
}
void uni(vel &a) {
vel ans(1, a[0]);
int n = a.size();
rep(i,n - 1) { if (a[i + 1] != a[i]) { ans.push_back(a[i + 1]); } }
a = ans;
}
int rui(int a, int n) {
if (n == 0) { return 1; }
int back = rui(a, n / 2);
back *= back; ref(back);
if (n % 2 == 0) { return back; }
return (back*a) % pr;
}
int inv(int a) {
return rui(a, pr - 2);
}
void pl(int &a, int b) {
ref(b);
a += b; ref(a);
}
signed main() {
int n; cin >> n;
vel a(n);
vel b(n);
vel all_time(1, 0);
rep(i, n) {
cin >> a[i] >> b[i]; b[i]++;
all_time.push_back(a[i]);
all_time.push_back(b[i]);
}
sort(all_time.begin(), all_time.end());
uni(all_time);
int sz = all_time.size();
vel gap(sz - 1);
rep(i, sz - 1) { gap[i] = all_time[i + 1] - all_time[i]; }
vel count(sz-1);
rep(i, n) {
a[i] = lower_bound(all_time.begin(), all_time.end(), a[i])-all_time.begin();
b[i] = lower_bound(all_time.begin(), all_time.end(), b[i])-all_time.begin();
rep(j, b[i] - a[i]) {
count[a[i] + j]++;
}
}
V<vel> com(sz-1);
rep(i, sz-1) {
int ba = 1;
rep(j, count[i]) {
ba *= gap[i] - j; ref(ba);
ba *= inv(j+1);
com[i].push_back(ba);
}
}
V<V<vel>> dp1(2, V<vel>(sz-1,vel(n)));
rep(i, n) {
int now = i % 2;
int nex = (i + 1) % 2;
dp1[nex] = dp1[now];
int sum = 1;
rep(j, a[i]) {
rep(k, count[j]) {
sum += dp1[now][j][k] * com[j][k];
ref(sum);
}
}
for (int j = a[i]; j < b[i]; j++) {
pl(dp1[nex][j][0],sum);
rep(k, count[j] - 1) {
pl(dp1[nex][j][k + 1], dp1[nex][j][k]);
}
rep(k, count[j]) {
sum += dp1[now][j][k] * com[j][k];
ref(sum);
}
}
}
int ans = 0;
rep(i, sz-1) {
rep(k, count[i]) {
ans += dp1[n%2][i][k] * com[i][k];
ref(ans);
}
}
cout << ans << endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
186 ms |
12408 KB |
Output is correct |
2 |
Correct |
196 ms |
12348 KB |
Output is correct |
3 |
Correct |
182 ms |
12288 KB |
Output is correct |
4 |
Correct |
200 ms |
12288 KB |
Output is correct |
5 |
Correct |
181 ms |
12408 KB |
Output is correct |
6 |
Correct |
187 ms |
12420 KB |
Output is correct |
7 |
Correct |
180 ms |
12328 KB |
Output is correct |
8 |
Correct |
215 ms |
12296 KB |
Output is correct |
9 |
Correct |
175 ms |
12288 KB |
Output is correct |
10 |
Correct |
188 ms |
12408 KB |
Output is correct |
11 |
Correct |
172 ms |
12328 KB |
Output is correct |
12 |
Correct |
194 ms |
12412 KB |
Output is correct |
13 |
Correct |
237 ms |
12408 KB |
Output is correct |
14 |
Correct |
181 ms |
12408 KB |
Output is correct |
15 |
Correct |
193 ms |
12288 KB |
Output is correct |
16 |
Correct |
39 ms |
2432 KB |
Output is correct |
17 |
Correct |
43 ms |
2680 KB |
Output is correct |
18 |
Correct |
39 ms |
2432 KB |
Output is correct |
19 |
Correct |
44 ms |
2680 KB |
Output is correct |
20 |
Correct |
41 ms |
2560 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
186 ms |
12408 KB |
Output is correct |
2 |
Correct |
196 ms |
12348 KB |
Output is correct |
3 |
Correct |
182 ms |
12288 KB |
Output is correct |
4 |
Correct |
200 ms |
12288 KB |
Output is correct |
5 |
Correct |
181 ms |
12408 KB |
Output is correct |
6 |
Correct |
187 ms |
12420 KB |
Output is correct |
7 |
Correct |
180 ms |
12328 KB |
Output is correct |
8 |
Correct |
215 ms |
12296 KB |
Output is correct |
9 |
Correct |
175 ms |
12288 KB |
Output is correct |
10 |
Correct |
188 ms |
12408 KB |
Output is correct |
11 |
Correct |
172 ms |
12328 KB |
Output is correct |
12 |
Correct |
194 ms |
12412 KB |
Output is correct |
13 |
Correct |
237 ms |
12408 KB |
Output is correct |
14 |
Correct |
181 ms |
12408 KB |
Output is correct |
15 |
Correct |
193 ms |
12288 KB |
Output is correct |
16 |
Correct |
39 ms |
2432 KB |
Output is correct |
17 |
Correct |
43 ms |
2680 KB |
Output is correct |
18 |
Correct |
39 ms |
2432 KB |
Output is correct |
19 |
Correct |
44 ms |
2680 KB |
Output is correct |
20 |
Correct |
41 ms |
2560 KB |
Output is correct |
21 |
Execution timed out |
2041 ms |
12800 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
49 ms |
980 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
186 ms |
12408 KB |
Output is correct |
2 |
Correct |
196 ms |
12348 KB |
Output is correct |
3 |
Correct |
182 ms |
12288 KB |
Output is correct |
4 |
Correct |
200 ms |
12288 KB |
Output is correct |
5 |
Correct |
181 ms |
12408 KB |
Output is correct |
6 |
Correct |
187 ms |
12420 KB |
Output is correct |
7 |
Correct |
180 ms |
12328 KB |
Output is correct |
8 |
Correct |
215 ms |
12296 KB |
Output is correct |
9 |
Correct |
175 ms |
12288 KB |
Output is correct |
10 |
Correct |
188 ms |
12408 KB |
Output is correct |
11 |
Correct |
172 ms |
12328 KB |
Output is correct |
12 |
Correct |
194 ms |
12412 KB |
Output is correct |
13 |
Correct |
237 ms |
12408 KB |
Output is correct |
14 |
Correct |
181 ms |
12408 KB |
Output is correct |
15 |
Correct |
193 ms |
12288 KB |
Output is correct |
16 |
Correct |
39 ms |
2432 KB |
Output is correct |
17 |
Correct |
43 ms |
2680 KB |
Output is correct |
18 |
Correct |
39 ms |
2432 KB |
Output is correct |
19 |
Correct |
44 ms |
2680 KB |
Output is correct |
20 |
Correct |
41 ms |
2560 KB |
Output is correct |
21 |
Execution timed out |
2041 ms |
12800 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |