Submission #395310

#	Time	Username	Problem	Language	Result	Execution time	Memory
395310		Nordway	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++17	0 / 100	1 ms	336 KiB

Main

#include<bits/stdc++.h>
#define x first
#define y second
#define pb push_back
#define mp make_pair
#define sz(v) v.size()
#define up_b upper_bound
#define low_b lower_bound
#define all(v) v.begin(),v.end()

using namespace std;

typedef long long ll;
typedef long double ld;

const int N=2e5+11;
const ll mod=1e9+7;
const ll INF=1e18;

ll a[N],b[N];
pair<ll,ll>dp1[N],dp2[N];

int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	
	int n;
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
		b[i]=a[i];
	}
	ll ans=0;
	ll cur=0;
	for(int i=1;i<=n;i++){
		if(b[i]>b[i-1]){
			cur=0;
			dp1[i]=mp(ans,cur);
		}
		else{
			if(b[i]+cur<=b[i-1]){
				ans+=b[i-1]-cur-b[i]+1;
				cur+=b[i-1]-cur-b[i]+1;
				b[i]=b[i-1]+1;
			}
			else{
				cur-=b[i]+cur-b[i-1]-1;
				b[i]=b[i-1]+1;
			}
			dp1[i]=mp(ans,cur);
		}
	}
	ans=0;
	cur=0;
	for(int i=1;i<=n;i++)b[i]=a[i];
	for(int i=n;i>=1;i--){
		if(b[i]>b[i+1]){
			cur=0;
			dp2[i]=mp(ans,cur);
		}
		else{
			if(b[i]+cur<=b[i+1]){
				ans+=b[i+1]-cur-b[i]+1;
				cur+=b[i+1]-cur-b[i]+1;
				b[i]=b[i+1]+1;
			}
			else{
				cur-=b[i]+cur-b[i+1]-1;
				b[i]=b[i+1]+1;
			}
			dp2[i]=mp(ans,cur);
		}
	}
	ll res=INF;
	for(int i=1;i<=n;i++){
		ll x=a[i]+min(dp1[i-1].y,dp2[i+1].y);
//		cout<<dp1[i-1].x<<" "<<dp2[i+1].x<<" "<<dp1[i-1].y<<" "<<dp2[i+1].y<<endl;
		res=min(res,dp1[i-1].x+dp2[i+1].x-min(dp1[i-1].y,dp2[i+1].y)+max(0ll,max(a[i+1],a[i-1])+1-x));
	}
	cout<<res;
	return 0;
}

• Subtask 1: 0 / 40
• Subtask 2: 0 / 60