제출 #1335456

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1335456		ttamx	Fancy Fence (CEOI20_fancyfence)	C++20	0 / 100	5 ms	448 KiB

fancyfence

#include<bits/stdc++.h>

using namespace std;

using ll = long long;

const int N=1e5+5;
const int MOD=1e9+7;

int n;
int h[N],w[N];
ll ans=0;

ll choose2(ll x){
    x%=MOD;
    return (x*(x-1)/2)%MOD;
}

int main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    cin >> n;
    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++){
        ans=(ans+choose2(h[i]+1)*choose2(h[i]+1)%MOD)%MOD;
    }
    for(int l=1;l<=n;l++){
        int mn=h[l];
        for(int r=l+1;r<=n;r++){
            mn=min(mn,h[r]);
            ans=(ans+choose2(mn+1)*w[l]%MOD*w[r]%MOD)%MOD;
        }
    }
    cout << ans << "\n";
}

• 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