Submission #329131

#	Time	Username	Problem	Language	Result	Execution time	Memory
329131		arayi	Xylophone (JOI18_xylophone)	C++17	0 / 100	1 ms	512 KiB

xylophone

#include "xylophone.h"
#include <algorithm>
#define qry query
using namespace std;


int n;
bool col[5050];
int a[5050];
int d(int a, int b, int c)
{
	return max(a, max(b, c)) - min(a, min(b, c));
}
void solve(int N) {

	n = N;
	int l = 1, r = n - 1, i1 = n - 1;
	while (l <= r)
	{
		int mid = (l + r) / 2;
		if (qry(mid, n) == n - 1) i1 = mid, l = mid + 1;
		else r = mid - 1;
	}
	a[i1] = 1;
	//printf("%d\n", i1);
	for (int i = i1 - 1; i > 0; i--)
	{
		int sm = qry(i, i + 1);
		if (a[i + 1] - sm < 1 || col[a[i + 1] - sm]) a[i] = a[i + 1] + sm;
		else if (a[i + 1] + sm > n || col[a[i + 1] + sm]) a[i] = a[i + 1] - sm;
		else
		{
			int sm1 = qry(i, i + 2);
			if (d(a[i + 1], a[i + 2], a[i] + sm) == sm1) a[i] = a[i + 1] + sm;
			else a[i] = a[i + 1] - sm;
		}
		col[a[i]] = 1;
	}
	for (int i = i1 + 1; i <= n; i++)
	{
		int sm = qry(i - 1, i);
		if (a[i - 1] - sm < 1 || col[a[i - 1] - sm]) a[i] = a[i - 1] + sm;
		else if (a[i - 1] + sm > n || col[a[i - 1] + sm]) a[i] = a[i - 1] - sm;
		else
		{
			int sm1 = qry(i - 2, i);
			if (d(a[i - 1], a[i - 2], a[i] + sm) == sm1) a[i] = a[i - 1] + sm;
			else a[i] = a[i - 1] - sm;
		}
		col[a[i]] = 1;
	}
	for (int i = 1; i <= n; i++) answer(i, a[i]);
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 36
• Subtask 3: 0 / 53