Submission #320796

#	Time	Username	Problem	Language	Result	Execution time	Memory
320796		mohamedsobhi777	Xylophone (JOI18_xylophone)	C++14	47 / 100	87 ms	644 KiB

xylophone

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

using namespace std;

int n;

int a1, an;

void dac(int l, int r)
{
        if (l + 1 == r)
        {
                a1 = l;
                an = r;
                return;
        }
        int mid = (l + r) >> 1;
        if (query(l, mid) == n - 1)
        {
                dac(l, mid);
        }
        else if (query(mid + 1, r) == n - 1)
        {
                dac(mid + 1, r);
        }
        else
        {

                int L = l, R = mid;
                while (L <= R)
                {
                        int m = (L + R) >> 1;
                        if (query(m, r) == n - 1)
                        {
                                a1 = m;
                                L = m + 1;
                        }
                        else
                                R = m - 1;
                }
                L = mid + 1, R = r;
                while (L <= R)
                {
                        int m = (L + R) >> 1;
                        if (query(l, m) == n - 1)
                        {
                                an = m;
                                R = m - 1;
                        }
                        else
                                L = m + 1;
                }
                return;
        }
}

int arr[10000];
int vis[10000];

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;
        }
}

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);
                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;
        }
}

void solve(int N)
{
        n = N;
        dac(1, N);
        arr[a1] = 1;
        arr[an] = N;
        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