Submission #1223851

#	Time	Username	Problem	Language	Result	Execution time	Memory
1223851		12baater	Cave (IOI13_cave)	C++20	0 / 100	79 ms	328 KiB

cave

#include "cave.h"
#include <vector>
#include <iostream>

using namespace std;

int switches[5050];
bool done[5050];
int door[5050];

void flip(int l, int r) {
    for (int i = l; i <= r; i++) {
        if (done[i]) continue;
        switches[i] = !switches[i];
    }
}

void exploreCave(int N) {
    vector<int> position(N);
    bool open = 0;
    for (int i = 0; i < N; i++) {
        // cout << i << "\n";
        int lower = 0, upper = N-1;
        int currentFirst = tryCombination(switches);
        open = (currentFirst == i);
        while (upper - lower > 0) {
            int mid = (upper-lower+1)>>1;
            // printf("Trying %d, %d\n", upper, lower);
            flip(lower, lower+mid);
            currentFirst = tryCombination(switches);
            if (open == (currentFirst == i)) {
                lower += mid;
            } else {
                upper = lower+mid-1;
            }
        }
        done[lower] = true;
        door[lower] = i;
    }
    answer(switches, door);
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 30
• Subtask 5: 0 / 24