#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define fi first
#define se second
const int maxn = 5e2+10;
const int MOD = (int)1e9+7;
pair<int,int> a[maxn];
unordered_map<int,int> dp[maxn];
int n;
int32_t main() {
cin >> n; int ans = 0;
for(int i = 0; i < n; i++) cin >> a[i].fi >> a[i].se;
for(int i = 0; i < n; i++){
for(int j = a[i].fi; j <= a[i].se; j++){
dp[i][j]=1;
if(j>a[i].fi) dp[i][j]+=dp[i][j-1];
if(dp[i][j]>MOD) dp[i][j]-=MOD;
for(int k = 0; k < i; k++){
if(j>a[k].fi) dp[i][j]+=dp[k][min(j-1,a[k].se)];
if(dp[i][j]>MOD) dp[i][j]-=MOD;
}
}
}
for(int i = 0; i < n; i++) ans+=dp[i][a[i].se], ans-=(ans>MOD?MOD:0);
cout << ans;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
3 ms |
340 KB |
Output is correct |
| 2 |
Correct |
4 ms |
340 KB |
Output is correct |
| 3 |
Correct |
4 ms |
340 KB |
Output is correct |
| 4 |
Correct |
4 ms |
340 KB |
Output is correct |
| 5 |
Correct |
3 ms |
340 KB |
Output is correct |
| 6 |
Correct |
6 ms |
340 KB |
Output is correct |
| 7 |
Correct |
7 ms |
340 KB |
Output is correct |
| 8 |
Correct |
6 ms |
368 KB |
Output is correct |
| 9 |
Correct |
7 ms |
344 KB |
Output is correct |
| 10 |
Correct |
6 ms |
396 KB |
Output is correct |
| 11 |
Correct |
6 ms |
340 KB |
Output is correct |
| 12 |
Correct |
6 ms |
340 KB |
Output is correct |
| 13 |
Correct |
6 ms |
340 KB |
Output is correct |
| 14 |
Correct |
6 ms |
340 KB |
Output is correct |
| 15 |
Correct |
6 ms |
340 KB |
Output is correct |
| 16 |
Correct |
4 ms |
340 KB |
Output is correct |
| 17 |
Correct |
4 ms |
340 KB |
Output is correct |
| 18 |
Correct |
3 ms |
340 KB |
Output is correct |
| 19 |
Correct |
3 ms |
340 KB |
Output is correct |
| 20 |
Correct |
4 ms |
340 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
3 ms |
340 KB |
Output is correct |
| 2 |
Correct |
4 ms |
340 KB |
Output is correct |
| 3 |
Correct |
4 ms |
340 KB |
Output is correct |
| 4 |
Correct |
4 ms |
340 KB |
Output is correct |
| 5 |
Correct |
3 ms |
340 KB |
Output is correct |
| 6 |
Correct |
6 ms |
340 KB |
Output is correct |
| 7 |
Correct |
7 ms |
340 KB |
Output is correct |
| 8 |
Correct |
6 ms |
368 KB |
Output is correct |
| 9 |
Correct |
7 ms |
344 KB |
Output is correct |
| 10 |
Correct |
6 ms |
396 KB |
Output is correct |
| 11 |
Correct |
6 ms |
340 KB |
Output is correct |
| 12 |
Correct |
6 ms |
340 KB |
Output is correct |
| 13 |
Correct |
6 ms |
340 KB |
Output is correct |
| 14 |
Correct |
6 ms |
340 KB |
Output is correct |
| 15 |
Correct |
6 ms |
340 KB |
Output is correct |
| 16 |
Correct |
4 ms |
340 KB |
Output is correct |
| 17 |
Correct |
4 ms |
340 KB |
Output is correct |
| 18 |
Correct |
3 ms |
340 KB |
Output is correct |
| 19 |
Correct |
3 ms |
340 KB |
Output is correct |
| 20 |
Correct |
4 ms |
340 KB |
Output is correct |
| 21 |
Execution timed out |
2077 ms |
21136 KB |
Time limit exceeded |
| 22 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Runtime error |
893 ms |
524288 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
3 ms |
340 KB |
Output is correct |
| 2 |
Correct |
4 ms |
340 KB |
Output is correct |
| 3 |
Correct |
4 ms |
340 KB |
Output is correct |
| 4 |
Correct |
4 ms |
340 KB |
Output is correct |
| 5 |
Correct |
3 ms |
340 KB |
Output is correct |
| 6 |
Correct |
6 ms |
340 KB |
Output is correct |
| 7 |
Correct |
7 ms |
340 KB |
Output is correct |
| 8 |
Correct |
6 ms |
368 KB |
Output is correct |
| 9 |
Correct |
7 ms |
344 KB |
Output is correct |
| 10 |
Correct |
6 ms |
396 KB |
Output is correct |
| 11 |
Correct |
6 ms |
340 KB |
Output is correct |
| 12 |
Correct |
6 ms |
340 KB |
Output is correct |
| 13 |
Correct |
6 ms |
340 KB |
Output is correct |
| 14 |
Correct |
6 ms |
340 KB |
Output is correct |
| 15 |
Correct |
6 ms |
340 KB |
Output is correct |
| 16 |
Correct |
4 ms |
340 KB |
Output is correct |
| 17 |
Correct |
4 ms |
340 KB |
Output is correct |
| 18 |
Correct |
3 ms |
340 KB |
Output is correct |
| 19 |
Correct |
3 ms |
340 KB |
Output is correct |
| 20 |
Correct |
4 ms |
340 KB |
Output is correct |
| 21 |
Execution timed out |
2077 ms |
21136 KB |
Time limit exceeded |
| 22 |
Halted |
0 ms |
0 KB |
- |
