Submission #534314

#	Time	Username	Problem	Language	Result	Execution time	Memory
534314		ac2hu	Untitled (POI11_tem)	C++14	24 / 100	1096 ms	17644 KiB

Main

#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")
#include <bits/stdc++.h>
#ifdef DEBUG
#include "../templates/debug.h"
#else 
#define deb(x...)
#endif
using namespace std;
template<class T> struct Seg { // comb(ID,b) = b
	const T ID = -1e9; T comb(T a, T b) { return max(a,b); }
	int n; vector<T> seg;
	void init(int _n) { n = _n; seg.assign(2*n,ID); }
	void pull(int p) { seg[p] = comb(seg[2*p],seg[2*p+1]); }
	void upd(int p, T val) { // set val at position p
		seg[p += n] = val; for (p /= 2; p; p /= 2) pull(p); }
	T query(int l, int r) {	// min on interval [l, r]
		T ra = ID, rb = ID;
		for (l += n, r += n+1; l < r; l /= 2, r /= 2) {
			if (l&1) ra = comb(ra,seg[l++]);
			if (r&1) rb = comb(seg[--r],rb);
		}
		return comb(ra,rb);
	}
};
signed main() {
	iostream::sync_with_stdio(false);
	cin.tie(nullptr);cout.tie(nullptr);
	int n;cin >> n;
	vector<pair<int,int>> a(n);
	for(auto &e : a)cin >> e.first >> e.second;
	Seg<int> rq;
	rq.init(n);
	for(int i = 0;i<n;i++){
		rq.upd(i,a[i].first);
	}
	vector<int> leftmost(n);
	for(int i =0;i<n;i++){
		int l = 0,r = i;
		while(l < r){
			int mid = (l + r)/2;
			if(rq.query(mid,i) <= a[i].second)
				r = mid;
			else
				l = mid + 1;
		}
		leftmost[i] = l;
	}
	for(int i = 1;i<leftmost.size();i++)
		leftmost[i] = max(leftmost[i], leftmost[i - 1]);
	for(int i = 0;i<n;i++)
		leftmost[i] = i - leftmost[i] + 1;
	deb(leftmost);
	cout << *max_element(leftmost.begin(),leftmost.end());
}

Compilation message (stderr)

tem.cpp: In function 'int main()':
tem.cpp:49:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |  for(int i = 1;i<leftmost.size();i++)
      |                ~^~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 8 / 8
• Subtask 4: 0 / 8
• Subtask 5: 0 / 8
• Subtask 6: 0 / 8
• Subtask 7: 0 / 8
• Subtask 8: 0 / 8
• Subtask 9: 0 / 9
• Subtask 10: 0 / 9
• Subtask 11: 0 / 9
• Subtask 12: 0 / 9