제출 #242100

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
242100		valerikk	Bigger segments (IZhO19_segments)	C++17	100 / 100	259 ms	29048 KiB

segments

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

#define int long long 

const int N = 5e5 + 7;

int t[4 * N];

void upd(int v, int l, int r, int ind, int val){
    if(r - l == 1)
        t[v] = val;
    else{
        int mid = (l + r) / 2;
        if(ind < mid){
            upd(2 * v, l, mid, ind, val);
        } else{
            upd(2 * v + 1, mid, r, ind, val);
        }
        t[v] = min(t[2 * v], t[2 * v + 1]);
    }
}

int get_ind(int v, int tl, int tr, int l, int r, int mx) {
    if(tl >= r || tr <= l || t[v] > mx)
        return -1;
    if(tr - tl == 1)
        return tl;
    int tm = (tl + tr) / 2;
    int ind = get_ind(2 * v + 1, tm, tr, l, r, mx);
    if(ind == -1)
        ind = get_ind(2 * v, tl, tm, l, r, mx);
    return ind;
}

int n, a[N], pref[N], cnt[N], lst[N];

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n;
    for(int i = 0; i < n; ++i){
        cin >> a[i];
        pref[i + 1] = pref[i] + a[i];
    }
    for(int i = 1; i <= n; ++i){
        int ind = get_ind(1, 0, n, 0, i, pref[i]);
        cnt[i] = cnt[ind] + 1;
        lst[i] = pref[i] - pref[ind];
        upd(1, 0, n, i, lst[i] + pref[i]);
    }
    cout << cnt[n];
    return 0;
}

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