Submission #709741

#	Time	Username	Problem	Language	Result	Execution time	Memory
709741		surgutti	Homecoming (BOI18_homecoming)	C++14	100 / 100	129 ms	55412 KiB

homecoming

#include <bits/stdc++.h>

using namespace std;

#include "homecoming.h"

long long solve(int N, int K, int *A, int *B) {

	long long cost = 0, ans = 0;
	for (int i = 0; i < K; i++)
		cost += B[i];

	long long take = A[0] - cost, leave = - 1E18L;

	ans = max(ans, take);
	ans = max(ans, leave);

	for (int i = 1; i < N; i++) {

		cost -= B[i - 1];
		int new_cost = 0;

		if (i + K - 1 < N)
			new_cost = B[i + K - 1];

		long long now_take = max(take, leave - cost) + A[i] - new_cost;
		long long now_leave = max(take, leave);

		cost += new_cost;

		take = now_take;
		leave = now_leave;

		ans = max(ans, take);
		ans = max(ans, leave);
	}

	cost = 0;
	for (int i = 0; i < K; i++)
		cost += B[i];

	take = A[0] - cost, leave = 0LL;

	ans = max(ans, take);
	ans = max(ans, leave);

	for (int i = 1; i < N; i++) {
		
		cost -= B[i - 1];
		int new_cost = B[(i + K - 1) % N];

		long long now_take = max(take, leave - cost) + A[i] - new_cost;
		long long now_leave = max(take, leave);

		cost += new_cost;

		take = now_take;
		leave = now_leave;

		ans = max(ans, take);
		ans = max(ans, leave);
	}

	return ans;
}

• Subtask 1: 13 / 13
• Subtask 2: 18 / 18
• Subtask 3: 31 / 31
• Subtask 4: 38 / 38