Submission #937525

#	Time	Username	Problem	Language	Result	Execution time	Memory
937525		Alcabel	Cave (IOI13_cave)	C++17	100 / 100	143 ms	604 KiB

cave

#include <bits/stdc++.h>
#include "cave.h"
using namespace std;

void exploreCave(int N) {
    vector<int> rest(N);
    iota(rest.begin(), rest.end(), 0);
    int S[N], D[N];
    for (int i = 0; i < N; ++i) {
        S[i] = 0;
    }
    for (int i = 0; i < N; ++i) {
        int start = tryCombination(S);
        if (start == -1) { start = N; }
        int left = 0, right = rest.size();
        while (right - left > 1) {
            int mid = left + (right - left) / 2;
            for (int j = left; j < mid; ++j) {
                S[rest[j]] = 1;
            }
            int closed = tryCombination(S);
            if (closed == -1) { closed = N; }
            for (int j = left; j < mid; ++j) {
                S[rest[j]] = 0;
            }
            if ((start == i && closed > i) || (start > i && closed == i)) {
                right = mid;
            } else {
                left = mid;
            }
        }
        D[rest[left]] = i;
        if (start == i) {
            S[rest[left]] = 1;
        } else {
            S[rest[left]] = 0;
        }
        swap(rest[left], rest.back());
        rest.pop_back();
    }
    answer(S, D);
}

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