Submission #777727

#	Time	Username	Problem	Language	Result	Execution time	Memory
777727		groshi	Fancy Fence (CEOI20_fancyfence)	C++17	0 / 100	1 ms	504 KiB

fancyfence

#include<bits/stdc++.h>
#define int long long
using namespace std;
int mod=1e9+7;
int h[200000];
int w[200000];
int licz(int x,int y)
{
    x+=y;
    ///x*(x+1)/2-y*(y+1)/2
    int jeden=x*(x+1)/2;
    int dwa=y*(y+1)/2;
    jeden-=dwa;
    jeden%=mod;
    jeden+=mod*mod;
    jeden%=mod;
    return jeden;
}
int32_t main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    int n;
    cin>>n;
    int wynik=0;
    vector<pair<int,int> > Q;
    for(int i=1;i<=n;i++)
        cin>>h[i];
    for(int i=1;i<=n;i++)
        cin>>w[i];
    for(int i=1;i<=n;i++)
    {
        int x=h[i];
        int y=w[i];
        int suma=0;
        while(Q.size() && Q.back().first>=x)
        {
            int cos1=(Q.back().first)*(Q.back().first+1);
            cos1/=2;
            cos1%=mod;
            int cos2=licz(Q.back().second,suma);
            cos1*=cos2;
            cos1%=mod;
            wynik+=cos1;
            wynik%=mod;
            suma+=Q.back().second;
            suma%=mod;
            Q.pop_back();
        }
        Q.push_back({x,(suma+y)%mod});
        //cout<<"wrzucam "<<x<<" "<<y<<"\n";
    }
    int suma=0;
    while(Q.size())
    {
        int cos1=(Q.back().first)*(Q.back().first+1);
        cos1/=2;
        cos1%=mod;
        //cout<<cos1<<"\n";
        int cos2=licz(Q.back().second,suma);
        cos1*=cos2;
        cos1%=mod;
        wynik+=cos1;
        //cout<<"dodaje "<<cos1<<"\n";
        wynik%=mod;
        suma+=Q.back().second;
        suma%=mod;
        Q.pop_back();
    }
    cout<<wynik;
    return 0;
}

• Subtask 1: 0 / 0
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27