Submission #786754

#	Time	Username	Problem	Language	Result	Execution time	Memory
786754		mindiyak	Roller Coaster Railroad (IOI16_railroad)	C++14	11 / 100	2075 ms	524288 KiB

railroad

#include "railroad.h"
#include <iostream>
#include <unordered_set>
#include <set>

#define ll long long

using namespace std;

const int MAXN = (2*1e5)+2;
// const int MAXN = 100;
vector<int> S;
vector<int> T;
long long ans = 1e18;

ll getCost(int start,int end){
    // cout << start << " " << end << " " << T[start] << " " << S[end] << endl;
    return max(0,T[start]-S[end]);
}

void dfs(int n,int pos,unordered_set<int> visited,ll cost){
    if(cost >= ans){
        return;
    }
    visited.insert(pos);
    if(visited.size() == n){
        ans = min(ans,cost);
        return;
    }

    set<pair<int,int>> possibilities;
    for(int i=0;i<n;i++){
        if(visited.count(i) == 0){
            possibilities.insert({getCost(pos,i),i});
        }
    }

    for(auto i : possibilities){
        // cout << i.first << " " << i.second << endl;
        // cout << pos << " " << i.second << " " << cost+i.first << endl;
        dfs(n,i.second,visited,cost+i.first);
    }
}

long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {

    // cout << endl;

    S=s;T=t;
    int n = (int) s.size();

    unordered_set<int> visited;
    for(int i=0;i<n;i++){
        dfs(n,i,visited,0);
    }

    return ans;
}

Compilation message (stderr)

railroad.cpp: In function 'void dfs(int, int, std::unordered_set<int>, long long int)':
railroad.cpp:26:23: warning: comparison of integer expressions of different signedness: 'std::unordered_set<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   26 |     if(visited.size() == n){
      |        ~~~~~~~~~~~~~~~^~~~

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