Submission #100193

#	Time	Username	Problem	Language	Result	Execution time	Memory
100193		luciocf	Boxes with souvenirs (IOI15_boxes)	C++14	25 / 100	6 ms	388 KiB

boxes

#include <bits/stdc++.h>
#include "boxes.h"
 
using namespace std;
 
const int maxn = 1e7+10;
 
typedef long long ll;
 
int p[maxn];
 
ll pref[maxn], suf[maxn];
 
long long delivery(int N, int K, int L, int positions[])
{
	int n = N, k = K;
	for (int i = 1; i <= n; i++)
		p[i] = positions[i-1];
 
	pref[1] = 2ll*p[1];
	for (int i = 2; i <= n; i++)
		pref[i] = 2ll*p[i] + pref[max(0, i-k)];
 
	suf[n] = 2ll*(L-p[n]);
	for (int i = n-1; i >= 1; i--)
		suf[i] = 2ll*(L-p[i]) + suf[min(n+1, i+k)];
 
	ll ans = min(pref[n], suf[1]);

	for (int i = 1; i < n; i++)
	{
		int add = (n-i)/k;
		if ((n-i)%k) add++;

		ans = min(ans, pref[i] + 1ll*add*L);
	}

	for (int i = n; i > 1; i--)
	{
		int add = (i-1)/k;
		if ((i-1)%k) add++;

		ans = min(ans, suf[i] + 1ll*add*L);
	}

	for (int i = 1; i < n; i++)
	{
		for (int j = i+1; j <= n; j++)
		{
			int add = (j-i-1)/k;
			if ((j-i-1)%k) add++;

			ans = min(ans, pref[i]+suf[j]+1ll*add*L);
		}
	}
 
	return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 10
• Subtask 3: 15 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30