Submission #287245

#	Time	Username	Problem	Language	Result	Execution time	Memory
287245		Saboon	Boxes with souvenirs (IOI15_boxes)	C++17	35 / 100	2 ms	384 KiB

boxes

#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1e7 + 10;
const ll inf = 1e18;
int n, k, L, a, b, A[maxn], B[maxn];
ll dp[maxn], pd[maxn], DP[maxn], opt[maxn];

void calc(int l, int r, int lo, int hi){
	if (l >= r)
		return;
	int m = (l+r) >> 1;
	DP[m] = inf;
	for (int i = lo; i < hi; i++){
		int cnt = n-m-i;
		int j = max(0, i - (k-(cnt%k))%k);
		cnt = (cnt+k-1)/k;
		ll x = 1LL*cnt*L + dp[m] + pd[j];
		if (x < DP[m])
			DP[m] = x, opt[m] = j;
		cnt = n-m-i;
		if (i + cnt%k <= b){
			j = i+(cnt%k);
			cnt -= cnt%k;
			cnt = cnt/k;
			x = 1LL*cnt*L + dp[m] + pd[j];
			if (x < DP[m])
				DP[m] = x, opt[m] = i;
		}
	}
	calc(l, m, lo, opt[m]+1);
	calc(m+1, r, opt[m], hi);
}

ll delivery(int N, int K, int LL, int p[]){
	n = N, k = K, L = LL;
	for (int i = 0; i < n; i++){
		if (p[i] <= L/2)
			A[++a] = p[i];
		else
			B[++b] = L-p[i];
	}
	sort(A+1,A+a+1);
	sort(B+1,B+b+1);
	for (int i = 1; i <= a; i++){
		if (i <= k)
			dp[i] = 2LL*A[i];
		else
			dp[i] = dp[i-k] + 2LL*A[i];
	}
	for (int i = 1; i <= b; i++){
		if (i <= k)
			pd[i] = 2LL*B[i];
		else
			pd[i] = pd[i-k] + 2LL*B[i];
	}
	calc(0, a+1, 0, b+1);
	return *min_element(DP, DP+a+1);
}

Compilation message (stderr)

boxes.cpp: In function 'void calc(int, int, int, int)':
boxes.cpp:32:23: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
   32 |  calc(l, m, lo, opt[m]+1);
      |                 ~~~~~~^~
boxes.cpp:33:20: warning: conversion from 'll' {aka 'long long int'} to 'int' may change value [-Wconversion]
   33 |  calc(m+1, r, opt[m], hi);
      |               ~~~~~^

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