Submission #720614

#	Time	Username	Problem	Language	Result	Execution time	Memory
720614		n1k	Roller Coaster Railroad (IOI16_railroad)	C++17	0 / 100	229 ms	16708 KiB

railroad

#include <bits/stdc++.h>

#define ll long long
#define vt vector
#define pb push_back
#define ar array
#define all(x) (x).begin(), (x).end()
#define sz(x) (x).size()

using namespace std;

/*
 1. simplify
 2. add new elements
 3. brute force solution
 4. optimize
 5. start implementing
*/

// --- templates ---
// --- code ---

#include "railroad.h"

long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
    int n = (int) s.size();
		set<ar<int, 2>> a;
	for(int i = 0; i < n; i++){
		a.insert({t[i], s[i]});
	}
	/*
	pick largest exit speed
	search for largest exit <= entry speed
	*/

	//auto [exit, entry] = *(--a.end());
	auto arr = *(--a.end());
	int exit = arr[0], entry = arr[1];
	a.erase(--a.end());
	while (sz(a)){
		auto it = a.lower_bound({entry + 1});
		if(it == a.begin()){
			return 1;
		}
		it--;
		arr = *it;
		exit = arr[0], entry = arr[1];

		a.erase(it);
	}
	return 0;
}

Compilation message (stderr)

railroad.cpp: In function 'long long int plan_roller_coaster(std::vector<int>, std::vector<int>)':
railroad.cpp:38:6: warning: variable 'exit' set but not used [-Wunused-but-set-variable]
   38 |  int exit = arr[0], entry = arr[1];
      |      ^~~~

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