Submission #751691

#	Time	Username	Problem	Language	Result	Execution time	Memory
751691		sofija6	Xylophone (JOI18_xylophone)	C++14	100 / 100	426 ms	456 KiB

xylophone

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

using namespace std;
static int A[5000];
bool check(int N)
{
    bool yes=true;
    int cnt[N+2]={0};
    for (int j=1;j<=N;j++)
        cnt[j]=0;
    for (int j=1;j<=N;j++)
    {
        if (A[j]<=N && A[j]>=1)
        {
            if ((A[j]==N && !cnt[1]) || cnt[A[j]])
                yes=false;
            cnt[A[j]]++;
        }
    }
    for (int j=1;j<=N;j++)
    {
        if (!cnt[j])
            yes=false;
    }
    return yes;
}
void solve(int N) {
    int diff2[N+2],diff3[N+2],cnt[N+2];
    for (int i=1;i<N;i++)
    {
        if (i<N-1)
            diff3[i]=query(i,i+2);
        diff2[i]=query(i,i+1);
    }
    for (int i=1;i<=N;i++)
    {
        int cur=1;
        A[1]=i;
        for (int j=2;j<=N;j++)
        {
            if (j>2 && N>2 && diff3[j-2]!=diff2[j-2]+diff2[j-1])
                cur*=(-1);
            A[j]=A[j-1]+diff2[j-1]*cur;
        }
        if (check(N))
        {
            for (int j=1;j<=N;j++)
                answer(j,A[j]);
            return;
        }
        cur=-1;
        for (int j=2;j<=N;j++)
        {
            if (j>2 && N>2 && diff3[j-2]!=diff2[j-2]+diff2[j-1])
                cur*=(-1);
            A[j]=A[j-1]+diff2[j-1]*cur;
        }
        if (check(N))
        {
            for (int j=1;j<=N;j++)
                answer(j,A[j]);
            return;
        }
    }
}

Compilation message (stderr)

xylophone.cpp: In function 'void solve(int)':
xylophone.cpp:29:31: warning: unused variable 'cnt' [-Wunused-variable]
   29 |     int diff2[N+2],diff3[N+2],cnt[N+2];
      |                               ^~~

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