Submission #945026

#	Time	Username	Problem	Language	Result	Execution time	Memory
945026		Xiaoyang	Fancy Fence (CEOI20_fancyfence)	C++17	13 / 100	12 ms	1884 KiB

fancyfence

#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
typedef long long ll;
 
#define fi first 
#define se second 
#define pll pair<ll,ll>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl;
#define MP make_pair
#define rep(i,a,b) for(ll i=a;i<b;i++)
#define SZ(x) (ll)x.size()
#define ALL(x) x.begin(),x.end()
#define endl "\n"
const ll inf=1e18;
ll lowbit(ll x){return x&(-x);}
 
const ll mod=1e9+7;
const ll maxn=1e5+5;
 
ll h[maxn],w[maxn];
 
ll c2(ll a){
	a%=mod;
	return (a*(a-1)/2)%mod;
}
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	ll n;cin>>n;
	ll wid=0;
	rep(i,1,n+1)cin>>h[i];
	rep(i,1,n+1)cin>>w[i],wid+=w[i],wid%=mod;
	
	ll ans=0;
	ans+=c2(wid+1);
	ans%=mod;
	//debug(ans);
	
	rep(i,1,n+1){
		if(h[i]==2){
			ll len=0;
			while(h[i]==2){
				len+=w[i];
				i++;
			}
			ans+=(2*c2(len+1))%mod;
			ans%=mod;
		}
	}
	cout<<ans<<endl;
	return 0;
}

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