Submission #320803

#	Time	Username	Problem	Language	Result	Execution time	Memory
320803		mohamedsobhi777	Xylophone (JOI18_xylophone)	C++14	47 / 100	94 ms	512 KiB

xylophone

#include "xylophone.h"
#include <bits/stdc++.h>

using namespace std;

int n;

int a1;
int arr[10000 + 5];
int vis[10000 + 5];

int ok(int x)
{
        if (x < 1 || x > n)
                return 0;
        return !vis[x];
}

void conLhs()
{
        if (a1 > 1)
                arr[a1 - 1] = query(a1 - 1, a1) + 1;
        for (int i = a1 - 2; i > 0; --i)
        {
                int q1 = query(i, i + 1);
                int q2 = abs(arr[i + 1] - arr[i + 2]);
                int q3 = query(i, i + 2);
                int sgn = ((q1 + q2 == q3 && arr[i + 1] > arr[i + 2]) ||
                                   (arr[i + 1] < arr[i + 2] && q1 + q2 != q3)
                               ? 1
                               : -1);
                arr[i] = arr[i + 1] + q1 * sgn;
                vis[arr[i]] = 1;
        }
}

void conMhs()
{
        if (a1 + 1 <= n)
                arr[a1 + 1] = query(a1, a1 + 1) + 1;
        for (int i = a1 + 2; i <= n; ++i)
        {
                int q1 = query(i - 1, i);
                if (ok(arr[i - 1] + q1) + ok(arr[i - 1] - q1) == 1 && 0)
                {
                        arr[i] = ok(arr[i - 1] + q1) ? arr[i - 1] + q1 : arr[i - 1] - q1;
                        vis[arr[i]] = 1;
                        continue;
                }
                int q2 = abs(arr[i - 1] - arr[i - 2]);
                int q3 = query(i - 2, i);
                int sgn = ((q1 + q2 == q3 && arr[i - 1] > arr[i - 2]) ||
                                   (arr[i - 1] < arr[i - 2] && q1 + q2 != q3)
                               ? 1
                               : -1);
                arr[i] = arr[i - 1] + q1 * sgn;
                vis[arr[i]] = 1;
        }
}

void solve(int N)
{
        n = N;
        int l = 1, r = N;
        vis[1] = 1;
        while (l <= r)
        {
                int mid = (l + r) >> 1;
                if (query(mid, N) == N - 1)
                {
                        a1 = mid;
                        l = mid + 1;
                }
                else
                        r = mid - 1;
        }
        arr[a1] = 1;

        conLhs();
        conMhs();
        for (int i = 1; i <= N; ++i)
        {
                answer(i, arr[i]);
                //printf("%d ", arr[i]);
        }
}

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