Submission #1208964

#	Time	Username	Problem	Language	Result	Execution time	Memory
1208964		dima2101	Growing Vegetables is Fun 4 (JOI21_ho_t1)	C++20	100 / 100	18 ms	6648 KiB

Main

#include <bits/stdc++.h>
#define int long long

signed main()
{
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);

    int n;
    std::cin >> n;

    std::vector<int> a(n);
    std::vector<int> d(n - 1);
    for (int i = 0; i < n; i++)
    {
        std::cin >> a[i];
    }
    for (int i = 0; i < n - 1; i++)
    {
        d[i] = (a[i + 1] - a[i]);
    }
    std::vector<int> pref(n - 1);
    for (int i = 0; i < n - 1; i++)
    {
        if (i == 0)
        {
            if (d[i] <= 0)
            {
                pref[i] = std::abs(d[i]) + 1;
            }
        }
        else
        {
            if (d[i] <= 0)
            {
                pref[i] = pref[i - 1] + std::abs(d[i]) + 1;
            }
            else
            {
                pref[i] = pref[i - 1];
            }
        }
    }
    std::vector<int> suf(n - 1);
    for (int i = n - 2; i >= 0; i--)
    {
        if (i == n - 2)
        {
            if (d[i] >= 0)
            {
                suf[i] = d[i] + 1;
            }
        }
        else
        {
            if (d[i] >= 0)
            {
                suf[i] = suf[i + 1] + d[i] + 1;
            }
            else
            {
                suf[i] = suf[i + 1];
            }
        }
    }

    int best = 1e15;
    best = std::min(pref.back(), suf[0]);
    for (int i = 1; i < n - 1; i++)
    {
        best = std::min(best, std::max(pref[i - 1], suf[i]));
    }
    std::cout << best;
}

• Subtask 1: 40 / 40
• Subtask 2: 60 / 60