#include<bits/stdc++.h>
using namespace std;
#define int long long
#define rep(i,n) for(int i=0;i<n;i++)
#define REP(i,n) for(int i=1;i<n;i++)
#define rev(i,n) for(int i=n-1;i>=0;i--)
#define all(v) v.begin(),v.end()
#define P pair<int,int>
#define len(s) (int)s.size()
template<class T> inline bool chmin(T &a, T b){
if(a>b){a=b;return true;}
return false;
}
template<class T> inline bool chmax(T &a, T b){
if(a<b){a=b;return true;}
return false;
}
constexpr int mod = 1e9+7;
constexpr long long inf = 3e18;
struct BIT{
int N;
vector<int>bit;
void add(int x,int y){
while(x<=N){
(bit[x]+=y)%=mod;x+=x&-x;
}
}
int sum(int x){
int res=0;
while(x>0){
(res+=bit[x])%=mod;x-=x&-x;
}
return res;
}
BIT(int x):N(x),bit(x+1){}
};
int N,A[505],B[505];
vector<int>x={0};
signed main(){
cin.tie(0);ios::sync_with_stdio(false);
cin>>N;
rep(i,N){
cin>>A[i]>>B[i];
x.push_back(A[i]-1);
x.push_back(A[i]);
x.push_back(B[i]);
}
sort(all(x));x.erase(unique(all(x)),x.end());
BIT bit(len(x));
bit.add(1,1);
rep(i,N){
B[i]=lower_bound(all(x),B[i])-x.begin()+1;
A[i]=lower_bound(all(x),A[i])-x.begin()+1;
for(int j=B[i];j>=A[i];j--){
int k=bit.sum(j-1)*(x[j-1]-x[j-2])%mod;
bit.add(j,k);
}
}
cout<<(bit.sum(len(x))-1+mod)%mod<<endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
404 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
1 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
1 ms |
384 KB |
Output is correct |
13 |
Correct |
2 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
416 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
404 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
1 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
1 ms |
384 KB |
Output is correct |
13 |
Correct |
2 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
416 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Incorrect |
10 ms |
384 KB |
Output isn't correct |
22 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
2 ms |
384 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
384 KB |
Output is correct |
2 |
Correct |
1 ms |
384 KB |
Output is correct |
3 |
Correct |
1 ms |
404 KB |
Output is correct |
4 |
Correct |
1 ms |
384 KB |
Output is correct |
5 |
Correct |
1 ms |
384 KB |
Output is correct |
6 |
Correct |
1 ms |
384 KB |
Output is correct |
7 |
Correct |
1 ms |
384 KB |
Output is correct |
8 |
Correct |
1 ms |
384 KB |
Output is correct |
9 |
Correct |
1 ms |
384 KB |
Output is correct |
10 |
Correct |
1 ms |
384 KB |
Output is correct |
11 |
Correct |
1 ms |
384 KB |
Output is correct |
12 |
Correct |
1 ms |
384 KB |
Output is correct |
13 |
Correct |
2 ms |
384 KB |
Output is correct |
14 |
Correct |
1 ms |
384 KB |
Output is correct |
15 |
Correct |
1 ms |
384 KB |
Output is correct |
16 |
Correct |
1 ms |
384 KB |
Output is correct |
17 |
Correct |
1 ms |
384 KB |
Output is correct |
18 |
Correct |
1 ms |
384 KB |
Output is correct |
19 |
Correct |
1 ms |
416 KB |
Output is correct |
20 |
Correct |
1 ms |
384 KB |
Output is correct |
21 |
Incorrect |
10 ms |
384 KB |
Output isn't correct |
22 |
Halted |
0 ms |
0 KB |
- |