#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {
cerr<<vars<<" = ";
string delim="";
(...,(cerr<<delim<<values,delim=", "));
cerr<<"\n";
}
#else
#define deb(...) logger(#__VA_ARGS__, __VA_ARGS__)
template<typename ...Args>
void logger(string vars, Args&&... values) {}
#endif
#define pb push_back
#define sz(x) (int)(x.size())
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
template<typename T> inline void maxa(T& a,T b){a=max(a,b);}
template<typename T> inline void mina(T& a,T b){a=min(a,b);}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int mxN=2e5+5; //make sure this is right
const int mod=1e9+7;
struct RANK{
vector<int> all;
int get(int x){return lower_bound(all.begin(),all.end(),x)-all.begin()+1;}
void add(int x){all.pb(x);}
void fix(){
sort(all.begin(),all.end());
all.resize(unique(all.begin(),all.end())-all.begin());
}
} rnk;
ll dp[505][1005],a[505],b[505];
int main(){
cin.sync_with_stdio(0);
cin.tie(0); cout.tie(0);
#ifdef LOCAL
freopen("input.txt","r",stdin);
freopen("output.txt","w",stdout);
#endif
rnk.add(1);
int n; cin>>n;
for(int i=1;i<=n;i++){
cin>>a[i]>>b[i];
rnk.add(a[i]);
rnk.add(b[i]);
rnk.add(b[i]+1);
rnk.add(a[i]+1);
rnk.add(a[i]-1);
rnk.add(b[i]-1);
}
rnk.fix();
dp[0][1]=1;
for(int i=1;i<=n;i++){
int A=a[i]; int B=b[i];
for(int j=1;j<=sz(rnk.all);j++){
ll ways=min(B,rnk.all[j-1]-1)-max(A,j==1?1:rnk.all[j-2])+1;
maxa(ways,0LL);
dp[i][j]=dp[i-1][j];
for(int k=j-1;k>=1;k--){
dp[i][j]+=(dp[i-1][k]*ways)%mod;
dp[i][j]%=mod;
}
// deb(i,j,dp[i][j]);
}
}
ll ans=0;
for(int i=2;i<=sz(rnk.all);i++)
ans=(ans+dp[n][i])%mod;
cout<<ans<<"\n";
}
// 4 + 7 + 7 + 6 + 5 + 4
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2079 ms |
3920 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2079 ms |
3920 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
75 ms |
1020 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
2079 ms |
3920 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |