Submission #906386

#	Time	Username	Problem	Language	Result	Execution time	Memory
906386		Trisanu_Das	Lightning Conductor (POI11_pio)	C++17	100 / 100	183 ms	14032 KiB

pio

#include <bits/stdc++.h>
using namespace std;
 
struct point {
	int i, l, r; //[l...r] => segment of maximality
};
 
int n, h[500005], dp[500005];
deque<point> hull;
 
double f(int x, int i) {
	return h[i] + sqrt(abs(x - i));
}
 
void solve() {
	hull.clear();
	for(int i = 1; i <= n; ++i) {
		while(!hull.empty() && hull.front().r < i) hull.pop_front();
		while(!hull.empty() && f(max(i, hull.back().l), hull.back().i) <= f(max(i, hull.back().l), i)) hull.pop_back();
		if(hull.empty()) hull.push_back({i, i, n});
		else {
			int l = max(i, hull.back().l), r = hull.back().r, ans = 0;
			while(l <= r) {
				int m = (l + r) / 2;
				if(f(m, i) >= f(m, hull.back().i)) ans = m, r = m - 1;
				else l = m + 1;
			}
			if(ans) {
				if(ans - 1 >= hull.back().l) hull.back().r = ans - 1;
				else hull.pop_back();
				hull.push_back({i, ans, n});
			}
		}
		dp[i] = max(dp[i], (int)ceil(f(i, hull.front().i)) - h[i]);
	}
}
 
int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
	cin >> n;
	for(int i = 1; i <= n; i++) cin >> h[i];
	solve();
	reverse(h + 1, h + 1 + n);
	reverse(dp + 1, dp + 1 + n);
	solve();
	for(int i = n; i; --i) cout << dp[i] << '\n';
}

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 9 / 9
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 10 / 10