Submission #497433

#	Time	Username	Problem	Language	Result	Execution time	Memory
497433		armashka	Bigger segments (IZhO19_segments)	C++17	13 / 100	1 ms	448 KiB

segments

#include <bits/stdc++.h>
 
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
#define fast ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define all(v) v.begin(),v.end()
#define pb push_back
#define sz size()
#define ft first
#define sd second
 
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef unsigned long long ull;
 
const int N = 1e6 + 5;
const ll M = 1e8;
const ll inf = 1e18;
const ll mod = 1e9;
const double Pi = acos(-1); 
 
ll binpow(ll x, ll ti) { ll res = 1;while (ti){if(ti & 1)res *= x;x *= x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll binmul(ll x, ll ti) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll nok(ll a, ll b) { return (a*b)/__gcd(abs(a),abs(b)) * (a*b > 0 ? 1 : -1); }
bool odd(ll n) { return (n % 2 == 1); }
bool even(ll n) { return (n % 2 == 0); }            

struct dinamika {
	ll cnt, sum;
} dp[N];

ll n, a[N], pr[N], t[N * 4];

void upd(ll pos, ll val, ll v = 1, ll tl = 1, ll tr = n) {
	if (tl == tr) {
		t[v] = val;
		return;
	} else {
		ll tm = (tl + tr) / 2;
		if (pos <= tm) upd(pos, val, v + v, tl, tm);
		else upd(pos, val, v + v + 1, tm + 1, tr);
		t[v] = max(t[v + v], t[v + v + 1]);
	}
}

pll get(ll l, ll r, ll v = 1, ll tl = 1, ll tr = n) {
	if (r < tl || tr < l) return {0, 0};
	if (tl == tr) return {t[v], tl};
	ll tm = (tl + tr) / 2;
	pll ans = {0, 0};
	if (t[v + v] > t[v + v + 1]) {
		ans = get(l, r, v + v, tl, tm);
		if (ans.ft == 0) ans = get(l, r, v + v + 1, tm + 1, tr);
	} else {
		ans = get(l, r, v + v + 1, tm + 1, tr);
		if (ans.ft == 0) ans = get(l, r, v + v, tl, tm);
	}
	return ans;
}

const void solve(/*Armashka*/) {
	cin >> n;
	for (int i = 1; i <= n; ++ i) {
		cin >> a[i];
		pr[i] = pr[i - 1] + a[i];
		dp[i] = {1, pr[i]};
		upd(i, dp[i].cnt);
	}
	for (int i = 1; i <= n; ++ i) {
		ll l = 1, r = i, j = 1;
		while (l <= r) {
			ll mid = (l + r) / 2;
			if (pr[i] - pr[mid - 1] >= dp[mid - 1].sum) l = mid + 1, j = mid;
			else r = mid - 1;
		}
		//cout << j << " ";
		pll ans = get(1, j - 1);
		dp[i] = {ans.ft + 1, pr[i] - pr[ans.sd]};
		//cout << dp[i].cnt << " ";
		upd(i, dp[i].cnt);
	}
	cout << dp[n].cnt << "\n";
}
            
signed main() {
    fast;
    //freopen("divide.in", "r", stdin);
    //freopen("divide.out", "w", stdout);
    int tt = 1;
    //cin >> tt;
    while (tt --) {                                                
        solve();
    }
}
 
/*
5 4 4
1 2
3 1
3 4
5 3
4 5 2 3
2 1 3 1
1 3 5
2 3 4 5
2 1 3 1
*/

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