Submission

Score: 100

User: 12345678

Problemset: รถไฟตู้เสบียง (Dining Car)

Language: cpp

Time: 0.002 second

Submitted On: 2026-02-13 10:26:48

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

using namespace std;

int a, b;

int findinside(int l, int r)
{
    while (l<r)
    {
        int md=(l+r)/2;
        if (compare_cars(md, md+1)==-1) r=md;
        else l=md+1;
    }
    return l;
}

pair<int, int> locate_dining_cars(int N) 
{
    int l=1, r=N;
    while (l<r)
    {
        int md=(l+r)/2; // the left side is abit smaller
        int side_query=compare_cars(l, r);
        if (side_query==0)
        {
            a=findinside(l, md);
            b=r-(a-l);
            return {a, b};
        }
        int mid_query=compare_cars(md, md+1);
        if (side_query==-1&&mid_query==-1) r=md;
        else if (side_query==1&&mid_query==1) l=md+1;
        else return {findinside(l, md), findinside(md+1, r)};
    }
    return {l ,l};
}