Submission #782507

#	Time	Username	Problem	Language	Result	Execution time	Memory
782507		Lyrically	Boxes with souvenirs (IOI15_boxes)	C++17	100 / 100	447 ms	199348 KiB

boxes

#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
long long pre[10000005],suf[10000005];
long long delivery(int n,int k,int l,int p[])
{
	rep(i,n)
	{
		if(p[i]<=l-p[i])
		{
			if(i<k){pre[i]=min(2*p[i],l);}
			else{pre[i]=pre[i-k]+min(2*p[i],l);}
		}
		else{pre[i]=pre[i-1];}
	}
	for(int i=n-1;i>=0;i--)
	{
		if(p[i]>l-p[i])
		{
			if(i+k-1<n)
			{
				suf[i]=suf[i+k]+min(2*(l-p[i]),l);
			}
			else
			{
				suf[i]=min(2*(l-p[i]),l);
			}
		}
		else{suf[i]=suf[i+1];}
	}
	long long res=pre[n-1]+suf[0];
	rep(i,n)
	{
		if(p[i]<=l-p[i])
		{
			if(i+k-1<n&&p[i+k-1]>l-p[i+k-1])
			{
				res=min(res,l+(i?pre[i-1]:0)+(i+k-1<n-1?suf[i+k]:0));
			}
		}
	}
	return res;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 30 / 30