Submission #1002083

#	Time	Username	Problem	Language	Result	Execution time	Memory
1002083		alecurse	Fancy Fence (CEOI20_fancyfence)	C++17	30 / 100	57 ms	2904 KiB

fancyfence

#include <bits/stdc++.h>
#define ll long long int
using namespace std;
ll mod = 1e9+7;
int main() {
    ll N;
    cin>>N;
    vector<ll> h(N+1), w(N+1),dpf(N+1);
    ll res=0;
    for(ll i=1;i<=N;i++) {
        cin>>h[i];
    }
    for(ll i=1;i<=N;i++) {
        cin>>w[i];
    }
    for(ll i=1;i<=N;i++) {
        ll sum=h[i]*(h[i]+(ll)1)/(ll)2;
        ll sumw=w[i]*(w[i]+(ll)1)/(ll)2;
        sum%=mod;
        sumw%=mod;
        dpf[i]=(sum*w[i])%mod+dpf[i-1];
        dpf[i]%=mod;
        res+=(sum*sumw)%mod;
        res+=(dpf[i-1]*w[i])%mod;
        res%=mod;
    }
    cout<<res;
}

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