Submission #440040

#	Time	Username	Problem	Language	Result	Execution time	Memory
440040		gromperen	Untitled (POI11_tem)	C++14	0 / 100	383 ms	33796 KiB

Main

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

#define ll long long

const int INF = 1e9+5;

struct segtree {
	vector<int> values;
	int size;
	void init(int n) {
		size = 1;
		while(size < n) size *= 2;
		values.resize(2*size);
	}
	void build(vector<int> &a, int x = 0, int lx = 0, int rx = -1) {
		if (rx == -1) rx = size;
		if (lx == rx) {
			if (lx < a.size())
				values[x] = a[lx];
			return;
		}
		int m = lx + ((rx - lx) >> 1);
		build(a, 2 * x, lx, m);
		build(a, 2 * x+1, m+1, rx);
		values[x] = max(values[2*x], values[2*x+1]);
	}

	int get(int l, int r, int x, int lx, int rx) {
		if (l <= lx && rx <= r) {
			return values[x];
		}
		int m = lx + ((rx - lx) >> 1), ret = 0;
		if (l <= m) {
			ret = max(ret, get(l, r, 2*x, lx, m));
		}
		if (m < r) {
			ret = max(ret, get(l, r, 2*x+1, m+1, rx));
		}
		return ret;
	}

	int get(int l, int r) {
		return get(l, r, 0, 0, size);
	}
};

int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);

	int n; cin >> n;
	vector<int> x(n), y(n);

	for (int i = 0; i < n; ++i) {
		cin >> x[i] >> y[i];
	}
	segtree st;
	st.init(n);
	st.build(x);
	int ans = 0;
	int l = 0;
	int maxx = -INF;
	for (int i = 0; i < n; ++i) {
		if (y[i] < maxx) {
			l++;
			int r = i;
			while (l < r) {
				int m = l + ((r - l) >> 1);
				int d = st.get(m, i);
				if (y[i] < d) {
					l = m+1;
				} else {
					r = m;
				}
			}
			maxx = st.get(l, i);
		}
		maxx = max(maxx, x[i]);
		ans = max(ans, i - l + 1);

	}
	cout << ans << "\n";



	return 0;
}

Compilation message (stderr)

tem.cpp: In member function 'void segtree::build(std::vector<int>&, int, int, int)':
tem.cpp:19:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |    if (lx < a.size())
      |        ~~~^~~~~~~~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 8
• Subtask 3: 0 / 8
• Subtask 4: 0 / 8
• Subtask 5: 0 / 8
• Subtask 6: 0 / 8
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• Subtask 8: 0 / 8
• Subtask 9: 0 / 9
• Subtask 10: 0 / 9
• Subtask 11: 0 / 9
• Subtask 12: 0 / 9