Submission #906672

#	Time	Username	Problem	Language	Result	Execution time	Memory
906672		imarn	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++14	100 / 100	25 ms	11928 KiB

Main

#include<bits/stdc++.h>
#define ll long long
#define pii pair<ll,ll>
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
using namespace std;
int main() {
    ios_base::sync_with_stdio(0);cin.tie(0);
    int n;cin>>n;
    ll a[n+1];
    for(int i=1;i<=n;i++)cin>>a[i];
    ll dpl[n+1];dpl[1]=0;
    for(int i=2;i<=n;i++)dpl[i]=dpl[i-1]+(a[i-1]-a[i]>=0?a[i-1]-a[i]+1:0);
    ll dpr[n+2]={0};dpr[n]=0;
    for(int i=n-1;i>=1;i--)dpr[i]=dpr[i+1]+(a[i+1]-a[i]>=0?a[i+1]-a[i]+1:0);
    ll ans=2e18;
    for(int i=1;i<=n;i++)ans=min(ans,max(dpl[i],dpr[i]));
    ll now[n+1];
    for(int i=1;i<=n;i++)now[i]=a[i];
    dpr[n]=0;ll cur=n-2,add=0;
    queue<pii>q;
    for(int i=n-1;i>=1;i--){
        while(!q.empty()&&q.front().f>i)add-=q.front().s,q.pop();
        now[i]+=add;
        dpr[i]=dpr[i+1]+max(now[i+1]-now[i]+1,1ll*0);
        int tt=max(now[i+1]-now[i]+1,1ll*0);
        now[i]+=tt;
        while(cur>0&&now[cur]<=now[i])q.push({cur--,tt}),add+=tt;
    }
    for(int i=1;i<=n-1;i++)ans=min(ans,dpl[i]+dpr[i+1]+max(now[i+1]-a[i]-dpl[i]+1,1ll*0));
    cout<<ans;
}

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