Submission #1309283

#	Time	Username	Problem	Language	Result	Execution time	Memory
1309283		elitewantsyou	Bigger segments (IZhO19_segments)	C++20	100 / 100	76 ms	35560 KiB

segments

#pragma GCC optimize("Ofast")

#include <bits/stdc++.h>

using namespace std;

const int N = 500500;

int n;
int a[N];
long long s[N];

int d[N];
vector<pair<long long, int>> v[N];

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        s[i] = s[i - 1] + a[i];
    }

    v[0].push_back({0, 0});
    for (int i = 1; i <= n; i++) {
        d[i] = d[i - 1];

        if (s[i] >= v[d[i]][0].first) {
            d[i] = d[i - 1] + 1;
        }
        int j = lower_bound(v[d[i] - 1].begin(), v[d[i] - 1].end(), make_pair(s[i] + 1, 0)) - v[d[i] - 1].begin() - 1;
        j = v[d[i] - 1][j].second;

        while (!v[d[i]].empty() && 2 * s[i] - s[j] < v[d[i]].back().first) {
            v[d[i]].pop_back();
        }

        assert (v[d[i]].empty() || 2 * s[i] - s[j] >= v[d[i]].back().first);

        v[d[i]].push_back({2 * s[i] - s[j], i});
    }

    cout << d[n] << "\n";
}

• Subtask 1: 13 / 13
• Subtask 2: 14 / 14
• Subtask 3: 10 / 10
• Subtask 4: 36 / 36
• Subtask 5: 27 / 27