Submission #1134986

#	Time	Username	Problem	Language	Result	Execution time	Memory
1134986		poat	Bigger segments (IZhO19_segments)	C++20	0 / 100	0 ms	328 KiB

segments

#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;

#define int long long
// #define mkp make_pair
#define txt freopen("kout.in", "r", stdin), freopen("kout.out", "w", stdout);
const int N = 200100, K = 20;
const int mod = 1e9 + 7;


void solve() 
{   
    int n;
    cin >> n;

    int arr[n];
    for(auto &i : arr) 
        cin >> i;
    int pref[n] = {arr[0]};
    for(int i = 1; i < n; i++)
        pref[i] += pref[i - 1] + arr[i];
    
    pair<int, int> dp[n + 5];
    dp[0] = {1, arr[0]};
    vector<pair<int, int>> vec;
    vec.push_back({dp[0].second, 0});
    for(int i = 1; i < n; i++)
    {
        dp[i] = {dp[i - 1].first, dp[i - 1].second + arr[i]};
        
        int l = -1, r = vec.size();
        while(r - l > 1)
        {
            int m = (l + r) / 2;
            if(pref[i] - pref[vec[m].second] >= vec[m].first)
                l = m;
            else
                r = m;
        }
        if(l != -1)
            dp[i] = {dp[vec[l].second].first + 1, pref[i] - pref[vec[l].second]};
        
        while(!vec.empty() && vec.back().first >= dp[i].second)
            vec.pop_back();
        vec.push_back({dp[i].second, i});
    }
     
    cout << dp[n - 1].first << '\n';
    

}



signed main()
{
    ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
    int T = 1;
    for (; T--; solve());
}

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