Submission #127941

#	Time	Username	Problem	Language	Result	Execution time	Memory
127941		Sorting	선물상자 (IOI15_boxes)	C++14	10 / 100	2 ms	380 KiB

boxes

#include <bits/stdc++.h>

using namespace std;

const int N = 1e7 + 7;

vector<long long> v1, v2;
vector<long long> v3, v4;

void output(vector<long long> v){
	for(long long &x: v){
		cout << x << " ";
	}
	cout << endl;
}

long long delivery(int n, int k, int l, int *positions){
	sort(positions, positions + n);
	
	int idx = 0;

	for(; idx < n && positions[idx] <= l / 2; idx++){
		v1.push_back(positions[idx]);
	}
	for(; idx < n; idx++){
		v2.push_back(l - positions[idx]);
	}
	if(!v2.empty()){
		reverse(v2.begin(), v2.end());
	}

	//output(v1);
	//output(v2);

	long long ans = 0;

	for(int i = -1; true;){
		if(i + k >= (int)v1.size()){
			for(++i; i < (int)v1.size(); ++i){
				v3.push_back(v1[i]);
			}
			break;
		}
		i += k;
		ans += (long long)v1[i] * 2ll;
	}
	for(int i = -1; true;){
		if(i + k >= (int)v2.size()){
			for(++i; i < (int)v2.size(); ++i){
				v4.push_back(v2[i]);
			}
			break;
		}
		i += k;
		ans += (long long)v2[i] * 2ll;
	}

	//output(v3);
	//output(v4);

	if(v3.empty() || v4.empty()){
		if(!v3.empty()){
			ans += v3.back() * 2ll;
		}
		if(!v4.empty()){
			ans += v4.back() * 2ll;
		}

		return ans;
	}

	if((int)v3.size() + (int)v4.size() <= k){
		ans += l;

		return ans;
	}

	int j = (int)v3.size() + (int)v4.size() - k;

	long long ans2 = ans + 2ll * (long long)l;

	if((int)v3.size() >= j){
		ans2 = min(ans2, v3[j - 1] * 2ll + (long long)l + ans);
	}
	if((int)v4.size() >= j){
		ans2 = min(ans2, v4[j - 1] * 2ll + (long long)l + ans);
	}
	ans2 = min(ans2, ans + v3.back() * 2ll + v4.back() * 2ll);

	return ans2;
}

/*int positions[N], n, k, l;

int main(){
	cin >> n >> k >> l;
	for(int i = 0; i < n; i++){
		cin >> positions[i];
	}

	cout << delivery(n, k, l, positions) << "\n";

	return 0;
}*/
/*
3 2 8
1 2 5
*/

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