Submission #1221062

#	Time	Username	Problem	Language	Result	Execution time	Memory
1221062		M_SH_O	Bigger segments (IZhO19_segments)	C++20	100 / 100	69 ms	15960 KiB

segments

#include <bits/stdc++.h>
//#include "grader.h"
/*#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>*/

#define ll long long
#define ll1 long long
#define ull unsigned long long
#define dou long double
#define str string
#define vll vector<ll>
#define vi vector<int>
#define pll pair<ll, ll>
#define vpll vector<pll>
#define vbool vector<bool>
#define vstr vector<str>
#define vvll vector<vll>
#define pb push_back
#define pf push_front
//#define endl "\n"
#define fr first
#define se second
// #define sortcmp(a) sort(a.begin(), a.end(), cmp)
#define sort(a) sort(a.begin(), a.end())
#define all(a) a.begin(), a.end()
#define reverse(a) reverse(a.begin(), a.end())
#define speed ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define INF 1000000000000000000
#define ordered_set tree<pll, null_type, less<pll>, rb_tree_tag, tree_order_statistics_node_update>

using namespace std;
//using namespace __gnu_pbds;

mt19937 rng(1488);
ll randll(ll l, ll r){
    return uniform_int_distribution<ll>(l, r)(rng);
}

int main() {
    srand(time(0));
    speed;

    ll n;
    cin >> n;
    vll a(n);
    vll pref(n+7, 0);
    for (int i =0 ; i < n; i ++) {
        cin >> a[i];
        pref[i+1] = pref[i];
        pref[i+1] += a[i];
    }

    vpll dp(n+7, {-1, -1});
    dp[0] = {1, 0};

    for (int i =0 ; i < n; i ++) {
        dp[i+1] = max(dp[i+1], dp[i]);
        ll s = pref[i+1]-pref[dp[i].se];
        ll l = i, r = n;
        while (r-l > 1) {
            ll x = (l+r)/2;
            if (pref[x+1]-pref[i+1] >= s) r = x;
            else l = x;
        }
        if (r != n) dp[r] = max(dp[r], {dp[i].fr+1, i+1});
    }

    cout << dp[n-1].fr << endl;
}

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