Submission #130936

#	Time	Username	Problem	Language	Result	Execution time	Memory
130936		antimirage	Boxes with souvenirs (IOI15_boxes)	C++14	100 / 100	763 ms	209264 KiB

boxes

#include "boxes.h"
//#include "grader.cpp"
#include <bits/stdc++.h>

#define fr first
#define sc second
#define mk make_pair
#define pb push_back
#define all(s) s.begin(), s.end()

using namespace std;

const int N = 1e7 + 5;

long long dp[N], mn = 1e18;

deque <pair < long long, int> > q, q2;

long long delivery(int n, int k, int l, int pos[]) {		
	memset(dp, 0x3f3f3f3f, sizeof(dp));
	int j = 0;
	
	for (int i = 0; i < n; i++) {
		
		while (j < i && pos[i] * 2 <= (l - pos[j + 1]) * 2) {
			while (!q2.empty() && q2.back().fr > dp[j] )
				q2.pop_back();
			
			q2.push_back({dp[j], j});
			j++;
		}
		while (!q2.empty() && q2.front().sc < i - k)
			q2.pop_front();
		
		while (!q.empty() && (q.front().sc < i - k || q.front().sc < j) )
			q.pop_front();
			
		if (i < k) {
			dp[i] = min( pos[i] * 2, min( l, (l - pos[0]) * 2 ) ) * 1ll;
		}
		if (i > 0) {
			if (q.empty())
				dp[i] = min( dp[i], q2.front().fr + min(pos[i] * 2, l) );
			else if (q2.empty())
				dp[i] = min( dp[i], q.front().fr );
			else 
				dp[i] = min(dp[i], min( q.front().fr, min(pos[i] * 2, l) + q2.front().fr ) );
		}
		if (i == n - 1)
			return dp[n - 1];
			
		while (!q.empty() && q.back().fr >= dp[i] + (l - pos[i + 1]) * 2)
			q.pop_back();
			
		q.push_back({dp[i] + (l - pos[i + 1]) * 2, i});
	}
}

Compilation message (stderr)

boxes.cpp: In function 'long long int delivery(int, int, int, int*)':
boxes.cpp:57:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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