Submission #1165874

#	Time	Username	Problem	Language	Result	Execution time	Memory
1165874		MPG	Bigger segments (IZhO19_segments)	C++20	100 / 100	112 ms	23916 KiB

segments

//#pragma GCC optomize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("O3")
//#pragma GCC target("avx2")
//#pragma GCC target("sse,sse2,sse4.1,sse4.2") 



#include <bits/stdc++.h>
using namespace std;
typedef long long       ll;
#define     max_heap priority_queue<pair <ll, pair <ll, ll>>>
#define     min_heap priority_queue<pair <ll, ll>, vector<pair <ll, ll>>, greater<pair <ll, ll>>>
#define     sariE cin.tie(NULL); cout.tie(NULL); ios_base::sync_with_stdio(false);
#define     filE freopen("in.txt", "r", stdin);// freopen("out1.txt", "w", stdout); 
#define     endl '\n'
#define     md(a) (a % mod + mod) % mod
#define     pb push_back
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
//cout << setprecision(5) << fixed << f;
//hash prime = 769


ll const maxn = 5e5 + 123;
ll const inf = 3e18;
ll const loG = 18; // 23
ll const mod = 1e9 + 7;
//ll const mod = 998244353;
ll const sq = 500;
ll power(ll a, ll b, ll mod){if(b==0)return 1;if(b==1)return a;ll x = power(a, b / 2, mod);return (((x * x) % mod) * (b % 2 ? a : 1)) % mod;}



ll n, ps[maxn], seg[maxn * 4], dp[maxn];

void setter(ll i, ll val, ll x, ll lx, ll rx){
    if (rx - lx == 1){
        seg[x] = val;
        return;
    }
    ll mid = (lx + rx) / 2, a = 2 * x + 1, b = a + 1;
    if (i < mid)
        setter(i, val, a, lx, mid);
    else
        setter(i, val, b, mid, rx);
    seg[x] = min(seg[a], seg[b]);
}

ll get(ll val, ll x, ll lx, ll rx){
    if (rx - lx == 1)
        return lx;
    ll mid = (lx + rx) / 2, a = 2 * x + 1, b = a + 1;
    if (seg[b] <= val){
        return get(val, b, mid, rx);
    }
    else
        return get(val, a, lx, mid);
}



void Solve(){

cin >> n;
for (int i = 1; i < n + 1; i++){
    cin >> ps[i];
    ps[i] += ps[i - 1];
}
for (int i = 0; i < maxn * 4; i++)
    seg[i] = inf;
for (int i = 1; i < n + 1; i++){
    ll j;
    if (seg[0] > ps[i]){
        j = 0;
    }
    else{
        j = get(ps[i], 0, 0, n + 1);
    }
    dp[i] = dp[j] + 1;
    //cout << i << ' ' << j <<  ' ' << dp[i] << endl;
    setter(i, ps[i] * 2 - ps[j], 0, 0, n + 1);
}
cout << dp[n] << endl;


}



int main(){
sariE;
//filE;



int test = 1;
//cin >> test;
while (test--) Solve();
return 0;
}

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