Submission #860994

#	Time	Username	Problem	Language	Result	Execution time	Memory
860994		Cookie	Bigger segments (IZhO19_segments)	C++14	100 / 100	86 ms	48152 KiB

segments

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
#define ll long long
#define vt vector
#define pb push_back
#define pii pair<int, int>
#define sz(dq) (int)dq.size()
#define forr(i, a, b) for(int i = a; i < b; i++)
#define fi first
#define se second
#define pll pair<ll, ll>
ifstream fin("store.inp");
ofstream fout("store.out");
const ll mxn = 5e5 + 5, inf = 1e9, mod = 1e9 + 7, sq = 800, mxv = 1e6 + 5, pr = 37, mod2 = 1e9 + 9, mod3 = 998244353;
//const int x[4] = {0, -1, 0, 1};
int n;
pll dp[mxn + 1];
ll a[mxn + 1], pref[mxn + 1];
vt<pll>events[mxn + 1];
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]; pref[i] = pref[i - 1] + a[i];
    }
    dp[0] = make_pair(0, 0);
    pair<ll, ll>mx = make_pair(0, 0);
    for(int i = 1; i <= n; i++){
        for(auto j: events[i]){
            mx = max(mx, j);
        }
        dp[i] = make_pair(mx.first + 1, pref[i] - pref[mx.second]);
        int l = i + 1, r = n, ans = n + 1;
        while(l <= r){
            int mid = (l + r) >> 1;
            if(pref[mid] - pref[i] >= pref[i] - pref[mx.second]){
                ans = mid; r = mid - 1;
            }else{
                l = mid + 1;
            }
        }
        events[ans].pb(make_pair(dp[i].first, i));
        
    }
    cout << dp[n].first;
    return(0);
}

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