Submission #711950

#	Time	Username	Problem	Language	Result	Execution time	Memory
711950		thimote75	Cave (IOI13_cave)	C++14	100 / 100	1049 ms	716 KiB

cave

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

#define MAX_N 5000

int currentDoor = 0;

static int S[MAX_N];
static int F[MAX_N];
static int D[MAX_N];

int nbSwitch;

void makeCombination (int left, int right, int t0, int t1) {
    int c = 0;
    for (int i = 0; i < nbSwitch; i ++) {
        if (F[i] != -1) {
            S[i] = F[i];
        } else {
            S[i] = left <= c && c <= right ? t1 : t0;
            c ++;
        }
    }
}
int nbTry = 0;
int tryComb (int left, int right, int t0, int t1) {
    makeCombination(left, right, t0, t1);

    int v = tryCombination(S);
    nbTry ++;

    if (v == -1) return nbSwitch + 1;
    return v;
}

int getValid (int door) {
    return tryComb(0, nbSwitch - 1 - door, 0, 1) > door ? 1 : 0;
}
int getDoor (int door, int target) {
    int n_target = 1 - target;

    int a = 0;
    int b = nbSwitch - 1 - door;

    while (a + 1 < b) {
        int c = (a + b) >> 1;

        if (tryComb(a, c, n_target, target) > door) {
            b = c;
        } else {
            a = c;
        }
    }

    int na = 0;
    int nb = 0;

    for (int i = a; i >= 0; na ++)
        i -= F[na] == -1 ? 1 : 0;
    for (int i = b; i >= 0; nb ++)
        i -= F[nb] == -1 ? 1 : 0;
    na --; nb --;

    return tryComb(a, a, n_target, target) > door ? na : nb;
}
#define di pair<int, int>
di getDoor (int door) {
    int target = getValid(door);

    return { getDoor(door, target), target };
}
void solve (int door) {
    di data = getDoor(door);
    
    int idSwitch = data.first;

    F[idSwitch] = data.second;
    D[idSwitch] = door;
}

void exploreCave(int N) {
    nbSwitch = N;

    for (int i = 0; i < N; i ++)
        F[i] = -1; // Signifies that it is not fixed

    for (int i = 0; i < N; i ++)
        solve(i);
    
    answer(F, D);
}

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