Submission #1235335

#	Time	Username	Problem	Language	Result	Execution time	Memory
1235335		ssitaram	Sails (IOI07_sails)	C++20	100 / 100	59 ms	1604 KiB

sails

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;

struct BIT {
	int n;
	vector<int> T;

	BIT(int sz) : n(sz), T(n + 1) {}

	void inc(int i, int v) {
		++i;
		for (; i <= n; i += i & -i) {
			T[i] += v;
		}
	}

	void incr(int l, int r) {
		if (l > r) return;
		inc(l, 1);
		inc(r + 1, -1);
	}

	int val(int i) {
		++i;
		int res = 0;
		for (; i > 0; i -= i & -i) {
			res += T[i];
		}
		return res;
	}
};

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	vector<pair<int, int>> masts(n);
	for (pair<int, int>& i : masts) cin >> i.first >> i.second;
	sort(masts.begin(), masts.end());
	BIT bit(masts.back().first);
	auto last = [&bit](int k) -> int {
		int lo = -1, hi = bit.n - 1;
		while (lo < hi) {
			int h = (lo + hi + 1) / 2;
			if (bit.val(h) > k) {
				hi = h - 1;
			} else {
				lo = h;
			}
		}
		return lo;
	};
	for (pair<int, int>& i : masts) {
		int st = bit.n - i.first;
		int en = st + i.second - 1;
		int a = max(last(bit.val(en) - 1) + 1, st);
		int b = last(bit.val(en));
		bit.incr(st, a - 1);
		int cnt = en - a + 1;
		bit.incr(b - cnt + 1, b);
	}
	ll ans = 0;
	for (int i = 0; i < bit.n; ++i) {
		ll cnt = bit.val(i);
		ans += cnt * (cnt - 1) / 2;
	}
	cout << ans << '\n';
	return 0;
}

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