Submission #760873

#	Time	Username	Problem	Language	Result	Execution time	Memory
760873		NK_	Bigger segments (IZhO19_segments)	C++17	100 / 100	64 ms	21336 KiB

segments

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>

using namespace std;

#define nl '\n'
#define f first
#define s second
#define mp make_pair
#define pb push_back

template<class T> using V = vector<T>;
using ll = long long;
using pl = pair<ll, int>;

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N; cin >> N;
	V<int> A(N); for(auto& x : A) cin >> x;

	V<ll> P = {0}; for(auto& x : A) P.pb(P.back() + x);
	V<int> ans(N + 1, 0);

	V<pl> X = {mp(0, 0)};

	for(int i = 1; i <= N; i++) {
		// FIND l such that P[l] + SUM[l] <= P[i]
		
		pl p = *prev(upper_bound(begin(X), end(X), mp(P[i], N + 1)));
		// cout << P[i] << " " << p.f << " " << p.s << nl;
		int l = p.s;

		ll x = P[i] + P[i] - P[l];
		ans[i] = ans[l] + 1;
		// cout << i << " " << l << " " << x << " " << ans[i] << nl;
		// cout << nl;

		while(X.back().f >= x) X.pop_back();
		X.pb(mp(x, i));
	}

	cout << *max_element(begin(ans), end(ans)) << nl;

    return 0;
}

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