Submission #801997

#	Time	Username	Problem	Language	Result	Execution time	Memory
801997		Johann	Mizuyokan 2 (JOI23_mizuyokan2)	C++14	15 / 100	4062 ms	6032 KiB

mizuyokan2

#include "bits/stdc++.h"
using namespace std;

typedef long long ll;
typedef vector<ll> vi;
typedef vector<vi> vvi;
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

const int INF = 1e9;

int N, Q;
vi L;

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

    cin >> N;
    L.resize(N);
    for (int i = 0; i < N; ++i)
        cin >> L[i];
    cin >> Q;

    while (Q--)
    {
        ll x, y, a, b;
        cin >> x >> y >> a >> b;
        --x;
        L[x] = y;
        vi B(L.begin() + a, L.begin() + b);
        // starting with lower piece
        vi dp(sz(B), -INF); // dp[i] := number of zigzag pieces in prefix i with i as minimum

        dp[0] = 1;
        for (int i = 1; i < sz(B); ++i)
        {
            ll buffer = 0;
            for (int j = i - 1; j >= 0; --j)
            {
                buffer += B[j];
                if (buffer > B[i])
                {
                    dp[i] = max(dp[i], 2LL);
                    if (j > 0 && buffer > B[j - 1])
                        dp[i] = max(dp[i], dp[j - 1] + 2);
                }
            }
        }

        ll ans = max(1LL, dp.back());
        ll buffer = 0;
        for (int i = sz(B) - 1; i > 0; --i)
        {
            buffer += B[i];
            if (buffer > B[i - 1])
                ans = max(ans, dp[i - 1] + 1);
        }

        cout << ans << "\n";
    }
}

• Subtask 1: 6 / 6
• Subtask 2: 9 / 9
• Subtask 3: 0 / 13
• Subtask 4: 0 / 32
• Subtask 5: 0 / 29
• Subtask 6: 0 / 11