Submission #722562

#	Time	Username	Problem	Language	Result	Execution time	Memory
722562		ymm	Roller Coaster Railroad (IOI16_railroad)	C++17	0 / 100	274 ms	17096 KiB

railroad

#include "railroad.h"
#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (ll)(r); ++x)
#define LoopR(x,l,r) for (ll x = (r)-1; x >= (ll)(l); --x)
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll , ll > pll;
using namespace std;

long long plan_roller_coaster(std::vector<int> s, std::vector<int> t)
{
	int n = s.size();
	set<pii> S;
	Loop (i,0,n)
		S.insert({s[i], i});
	int cnt = 0;
	int ds;
	vector<pii> vec;
	while (S.size()) {
		int i = S.begin()->second;
		int is = s[i], it = t[i];
		S.erase(S.begin());
		while (is < it) {
			auto p = S.lower_bound(pii{it, INT_MIN});
			if (p == S.end()) {
				++cnt;
				ds = is;
				break;
			}
			int j = p->second;
			S.erase(p);
			it = t[j];
			vec.push_back({it, is});
		}
	}
	if (cnt > 1)
		return 1;
	if (cnt == 0)
		return 0;
	sort(vec.begin(), vec.end());
	for (auto [x, y] : vec) {
		if (x > ds)
			return 1;
		ds = max(ds, y);
	}
	return 0;
}

Compilation message (stderr)

railroad.cpp: In function 'long long int plan_roller_coaster(std::vector<int>, std::vector<int>)':
railroad.cpp:17:6: warning: 'ds' may be used uninitialized in this function [-Wmaybe-uninitialized]
   17 |  int ds;
      |      ^~

• Subtask 1: 0 / 11
• Subtask 2: 0 / 23
• Subtask 3: 0 / 30
• Subtask 4: 0 / 36