Submission #947612

#	Time	Username	Problem	Language	Result	Execution time	Memory
947612		4QT0R	Boxes with souvenirs (IOI15_boxes)	C++17	100 / 100	459 ms	293672 KiB

boxes

#include <bits/stdc++.h>
using namespace std;
#define ll long long

ll pref[10000002];
ll suf[10000002];

ll delivery(int n, int k, int l, int positions[]){
	for (int i = 0; i<k; i++)pref[i]=positions[i];
	for (int i = k; i<n; i++)pref[i]=positions[i]+pref[i-k];
	for (int i = n-1; i>n-k-1; i--)suf[i]=l-positions[i];
	for (int i = n-k-1; i>=0; i--)suf[i]=l-positions[i]+suf[i+k];
	ll ans=min(2*suf[0],l+2*suf[k]);
	for (int i = 0; i<n; i++)ans=min(ans,2*pref[i]+2*suf[i+1]);
	for (int i = 1; i<n; i++)ans=min(ans,2*pref[i-1]+l+2*(i+k<n?suf[i+k]:0));
	return ans;
}

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