Submission #726033

#	Time	Username	Problem	Language	Result	Execution time	Memory
726033		adrilen	Rice Hub (IOI11_ricehub)	C++17	100 / 100	94 ms	2884 KiB

ricehub

#include "ricehub.h"
#include<bits/stdc++.h>
using namespace std;
using ll = long long;
typedef pair<int, int> pii;


int besthub(int n, int L, int X[], long long b)
{
    vector <ll> fields;
    for (int i = 0; i < n; i++) fields.emplace_back(X[i]);


    if (n <= 5e3)
    {
        ll cur = 0;
        if (n == 1) return 1;
        int output = 0;

        ll p;
        int left, right;
        for (int i = 0; i < n; i++)
        {
            p = fields[i];
            cur = b;
            left = i - 1, right = i + 1;

            while (true)
            {
                if (left < 0 && right == n)
                {
                    break;
                } else if (left < 0)
                {   
                    if (cur >= fields[right] - p) {
                        cur -= fields[right] - p;
                        right++;
                    } else break;
                } else if (right == n)
                {
                    if (cur >= p - fields[left]) {
                        cur -= p - fields[left];
                        left--;
                    } else break;
                }
                else if (p - fields[left] < fields[right] - p)
                {
                    if (cur >= p - fields[left]) {
                        cur -= p - fields[left];
                        left--;
                    } else break;
                } else {
                    if (cur >= fields[right] - p) {
                        cur -= fields[right] - p;
                        right++;
                    } else break;
                }
            }
            output = max(output, right - left - 1);
        }
        return output;
    }

    auto pos = fields.begin(), lt = fields.begin(), rt = fields.begin() + 1;
    ll cur = 0;
    if (n == 1) return 1;
    long output = 0;


    while (rt != fields.end())
    {
        while (cur > b)
        {
            cur -= *pos - *lt;
            lt++;
        }

        while (rt != fields.end() && cur + (*rt - *pos) <= b)
        {
            cur += (*rt - *pos);
            rt++;
        }

        while (rt != fields.end() && (*pos - *lt) > (*rt - *pos))
        {
            cur += (*rt - *pos) - (*pos - *lt); 
            lt++, rt++;
            while (rt != fields.end() && cur + (*rt - *pos) <= b)
            {
                cur += (*rt - *pos);
                rt++;
            }        
        }

        output = max(output, ((rt - fields.begin()) - (lt - fields.begin())));
        
        pos++;
        if (rt != fields.end())
        {
            cur += (*pos - *(pos - 1)) * ((pos - fields.begin()) - (lt - fields.begin()));
            cur += (*(pos - 1) - *pos) * ((rt - fields.begin()) - (pos - fields.begin()));
        }
    }
    // cerr << output << "\n";
    return output;
}

• Subtask 1: 17 / 17
• Subtask 2: 25 / 25
• Subtask 3: 26 / 26
• Subtask 4: 32 / 32