제출 #542444

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
542444		status_coding	Xylophone (JOI18_xylophone)	C++14	0 / 100	1 ms	208 KiB

xylophone

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

using namespace std;

int n;
int a[5005];

map<int, int> fr;

int findN()
{
    int st=2, dr=n, mij, last;
    while(st <= dr)
    {
        mij = (st+dr)/2;

        //cout<<1<<' '<<mij<<'\n';

        if(query(1, mij) == n-1)
        {
            last=mij;
            dr=mij-1;
        }
        else
            st=mij+1;
    }

    return last;
}

bool bad(int x)
{
    if(x > n)
        return true;
    if(x < 0)
        return true;
    if(fr[x])
        return true;

    return false;
}

void solve(int N)
{
    n=N;

    int p = findN();
    a[p] = n;
    fr[n]=1;

    int mini=n;

    for(int i=p-1;i>=1;i--)
    {
        int dif = query(i, i+1);

        int x1 = a[i+1] - dif;
        int x2 = a[i+1] + dif;

        if(bad(x1))
            a[i]=x2;
        else if(bad(x2))
            a[i]=x1;
        else
        {
            int nQ = query(i, p);

            if(nQ > n - mini)
                a[i]=n-nQ;
            else
                a[i]=x2;
        }

        mini=min(mini, a[i]);
        fr[ a[i] ] =1;
    }

    mini=n;
    for(int i=p+1;i<=n;i++)
    {
        int dif = query(i-1, i);

        int x1 = a[i-1] - dif;
        int x2 = a[i-1] + dif;

        if(bad(x1))
            a[i]=x2;
        else if(bad(x2))
            a[i]=x1;
        else
        {
            int nQ = query(p, i);

            if(nQ > n - mini)
                a[i]=n-nQ;
            else
                a[i]=x2;
        }

        mini=min(mini, a[i]);
        fr[ a[i] ] =1;
    }

    /*
    for(int i=1;i<=n;i++)
        cout<<a[i]<<' ';
    */

    for(int i=1;i<=n;i++)
        answer(i, a[i]);
}

컴파일 시 표준 에러 (stderr) 메시지

xylophone.cpp: In function 'int findN()':
xylophone.cpp:29:12: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized]
   29 |     return last;
      |            ^~~~
xylophone.cpp: In function 'void solve(int)':
xylophone.cpp:54:13: warning: 'last' may be used uninitialized in this function [-Wmaybe-uninitialized]
   54 |     for(int i=p-1;i>=1;i--)
      |             ^

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