Submission #678120

#	Time	Username	Problem	Language	Result	Execution time	Memory
678120		Alcabel	Bigger segments (IZhO19_segments)	C++17	13 / 100	1 ms	324 KiB

segments

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

void solve() {
    int n;
    cin >> n;
    vector<int> a(n);
    vector<long long> pref(n + 1);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        pref[i + 1] = pref[i] + a[i];
    }
    vector<pair<int, long long>> f(n + 1);
    f[0] = {0, 0};
    for (int i = 1, lower = 0, cur = 0; i <= n; ++i) {
        int l = cur - 1, r = i;
        while (r - l > 1) {
            int m = l + (r - l) / 2;
            if (f[m].second <= pref[i] - pref[m]) {
                l = m;
            } else {
                r = m;
            }
        }
        if (l != cur - 1) {
            f[i] = {f[cur].first + 1, pref[i] - pref[l]};
            lower = cur, cur = i;
        } else {
            l = lower - 1, r = cur;
            while (r - l > 1) {
                int m = l + (r - l) / 2;
                if (f[m].second <= pref[i] - pref[m]) {
                    l = m;
                } else {
                    r = m;
                }
            }
            assert(l != lower - 1);
            f[i] = {f[cur].first, pref[i] - pref[l]};
        }
        // cerr << "i: " << i << ", f: " << f[i].first << ", " << f[i].second << '\n';
    }
    cout << f[n].first << '\n';
}

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

    int T = 1;
    // cin >> T;
    while (T--) {
        solve();
    }

    return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 0 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27