Submission #890464

#	Time	Username	Problem	Language	Result	Execution time	Memory
890464		Sorting	Cave (IOI13_cave)	C++17	100 / 100	178 ms	816 KiB

cave

#include <iostream>
#include <vector>
#include <algorithm>
#include <numeric>
#include <map>
#include <set>
#include <queue>
#include <array>
#include <stack>
#include <cmath>
#include <iomanip>
#include <cassert>
#include "cave.h"

using namespace std;

typedef long long ll;

void answer(int S[], int D[]);
int tryCombination(int S[]);

int s[6000], d[6000];
void exploreCave(int n){
    vector<int> active(n);
    iota(active.begin(), active.end(), 0);

    for(int i = 0; i < n; ++i){
        int l = 0, r = (int)active.size() - 1;

        for(int x: active)
            s[x] = 0;

        int prv = tryCombination(s);

        while(l != r){
            int mid = (l + r) >> 1;

            for(int i = 0; i <= mid; ++i)
                s[active[i]] = 1;
            for(int i = mid + 1; i < active.size(); ++i)
                s[active[i]] = 0;

            if((tryCombination(s) == i) != (prv == i)){
                r = mid;
            }
            else{
                l = mid + 1;
            }
        }

        int key = active[l];
        active.erase(find(active.begin(), active.end(), key));

        if(prv == i){
            s[key] = 1;
        }
        else{
            s[key] = 0;
        }
        d[key] = i;
    }
    answer(s, d);
}

Compilation message (stderr)

cave.cpp: In function 'void exploreCave(int)':
cave.cpp:40:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |             for(int i = mid + 1; i < active.size(); ++i)
      |                                  ~~^~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 13 / 13
• Subtask 3: 21 / 21
• Subtask 4: 30 / 30
• Subtask 5: 24 / 24