Submission #704076

#	Time	Username	Problem	Language	Result	Execution time	Memory
704076		Potato3218	Cave (IOI13_cave)	C++17	100 / 100	368 ms	588 KiB

cave

#include "cave.h"
#include <bits/stdc++.h>
using namespace std;
int switches[5006];
int sToDoors[5006];
int tryDoors[5006];
void solveDoor(int door, int N){
    for (int i = 0; i < N; i++){
       	if(switches[i] == -1) tryDoors[i] = 0;
		else tryDoors[i] = switches[i];
    }
    int d = tryCombination(tryDoors);
    int is_open;
	if(d==door) is_open = 0;
	else is_open = 1;
    int mini = -1;
    int maxi = N;
    while (maxi - mini > 1){
        int mid = (maxi + mini) / 2;
        for (int i = 0; i < mid; i++){
            if(switches[i] == -1) tryDoors[i] = 1;
		    else tryDoors[i] = switches[i];
        }
        int firstDoor = tryCombination(tryDoors);
        if (is_open == 1 && firstDoor != door) mini = mid;
        else if (is_open == 0 && firstDoor == door) mini = mid;
        else maxi = mid;
        for (int i = 0; i < mid; i++){
            if(switches[i] == -1) tryDoors[i] = 0;
		    else tryDoors[i] = switches[i];
        }
    }
    sToDoors[mini] = door;
    switches[mini] = !is_open;
}
void exploreCave(int N) {
    memset(switches, -1, sizeof switches);
    for (int i = 0; i < N; i++){
        solveDoor(i, N);
    }
    answer(switches, sToDoors);
}

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