Submission #129212

#	Time	Username	Problem	Language	Result	Execution time	Memory
129212		joseacaz	Boxes with souvenirs (IOI15_boxes)	C++17	0 / 100	2 ms	376 KiB

boxes

#include "boxes.h"
#include <bits/stdc++.h>
#define MAXN 1000015
#define INF (1LL << 60LL)

using namespace std;
typedef long long ll;

int N, K, L, lbound;
ll DP[MAXN], pre[MAXN], cost, ST[2 * MAXN];
vector < int > P;

void build ()
{
	for ( int i = 0; i <= 2 * (N + 5); i++ )
		ST[i] = INF;
}

ll qry ( int l, int r )
{
	ll ans = INF;
	for ( l += N + 1, r += N + 2; l < r; l>>=1, r>>=1 )
	{
		if ( l & 1 )
			ans = min ( ans, ST[l++] );
		if ( r & 1 )
			ans = min ( ans, ST[--r] );
	}
	return ans;
}

void upd ( int pos, ll x )
{
	for ( pos += N + 1; pos; pos>>=1 )
		ST[pos] = min ( ST[pos], x );
}

ll delivery ( int _n, int _k, int _l, int _p[] )
{
	N = _n, K = _k, L = _l;
	P.push_back ( 0 );
	for ( int i = 0; i < N; i++ )
		P.push_back ( _p[i] );
	P.push_back ( L );
	
	for ( int i = 1; i <= N + 1; i++ )
	{
		pre[i] = pre[i - 1] + (P[i] - P[i - 1]);
		if ( 2 * P[i] < L )
			lbound = i;
	}
	
	build();
	upd ( N + 1, 0 );
	for ( int i = N; i >= 1; i-- )
	{
		if ( i <= lbound + 1 )
		{
			DP[i] = min ( qry ( i + 1, lbound + 1 ), qry ( lbound + 2, i + K ) + min ( (ll)L, 2 * (pre[N + 1] - pre[i]) ) ), upd ( i, DP[i] + 2 * pre[i - 1] );
		}
		else
			DP[i] = qry ( i + 1, i + K ) + min ( (ll)L, 2 * (pre[N + 1] - pre[i]) ), upd ( i, DP[i] );
	}

	return DP[1];
}

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