Submission #219471

#	Time	Username	Problem	Language	Result	Execution time	Memory
219471		MKopchev	Xylophone (JOI18_xylophone)	C++14	100 / 100	1407 ms	1272 KiB

xylophone

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

using namespace std;
const int nmax=5e3+42;

int output[nmax];
int n;
bool seen[nmax];

int diff[nmax],diff_2[nmax];
/*
int query(int s,int t)
{
    cout<<s<<" "<<t<<endl;
    int ret;
    cin>>ret;
    return ret;
}

int answer(int s,int t)
{
    cout<<"answer "<<s<<" "<<t<<endl;
}
*/
int my_ask(int s,int t)
{
    return query(s,t);
}

int maxi(vector<int> now)
{
    int a=0;
    for(auto k:now)
        a=max(a,k);
    return a;
}
int mini(vector<int> now)
{
    int a=nmax;
    for(auto k:now)
        a=min(a,k);
    return a;
}

bool STOP;
void print()
{
    for(int i=1;i<=n;i++)
        answer(i,output[i]);
    STOP=1;
}

void rec(int val,int pos)
{
    //cout<<"rec "<<val<<" "<<pos<<endl;

    if(STOP)return;

    if(1>val||val>n)return;
    if(seen[val])return;

    seen[val]=1;
    output[pos]=val;

    if(val==n&&seen[1]==0)
    {
        seen[val]=0;
        return;
    }

    //cout<<"rec: ";for(int i=1;i<=n;i++)cout<<output[i]<<" ";cout<<";"<<endl;for(int i=1;i<=n;i++)cout<<seen[i]<<" ";cout<<endl;

    if(diff_2[pos])
    {
        //cout<<"test_2 "<<maxi({output[pos-2],output[pos-1],output[pos]})<<" "<<mini({output[pos-2],output[pos-1],output[pos]})<<" "<<diff_2[pos]<<endl;

        if(maxi({output[pos-2],output[pos-1],output[pos]})-mini({output[pos-2],output[pos-1],output[pos]})!=diff_2[pos])
        {
            seen[val]=0;
            return;
        }
    }

    if(pos==n)print();

    rec(val+diff[pos],pos+1);

    rec(val-diff[pos],pos+1);

    seen[val]=0;
}
void solve(int N)
{
    n=N;

    for(int i=1;i+1<=n;i++)
        diff[i]=my_ask(i,i+1);

    for(int i=3;i<=n;i++)
        diff_2[i]=my_ask(i-2,i);

    for(int i=1;i<=n;i++)
        rec(i,1);
}
/*
int main()
{
    solve(5);
}
*/

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