Submission #1104192

#	Time	Username	Problem	Language	Result	Execution time	Memory
1104192		Ianis	Cave (IOI13_cave)	C++17	100 / 100	232 ms	700 KiB

cave

#pragma GCC optimize("Ofast,unroll-loops")
#include "cave.h"
#include <iostream>

using namespace std;

const int NMAX = 5005;

int n;
int a[NMAX];
int ans[NMAX];
int pos[NMAX];
int swi[NMAX];

int query(int s[]) {
   int q = tryCombination(s);
   return q == -1 ? n : q;
}

void make_seq(bool val, short l, short r, int cnt) {
   fill(a, a + n, !val);
   fill(a + l, a + r + 1, val);
   for (int i = 0; i < cnt; i++) {
      a[swi[i]] = ans[swi[i]];
   }
}

int find_switch(int door) {
   int l = 0, r = n - 1;
   bool val = 1;

   make_seq(1, 0, n - 1, door);
   if (query(a) <= door) {
      val = 0;
   }

   while (l <= r) {
      int mid = (l + r) >> 1;
      make_seq(val, l, mid, door);
      if (query(a) <= door) {
         l = mid + 1;
      } else {
         r = mid - 1;
      }
   }

   swi[door] = r + 1;
   ans[r + 1] = val;

   return r + 1;
}

void exploreCave(int N) {
   n = N;

   for (int i = 0; i < n; i++) {
      int x = find_switch(i);
      pos[x] = i;
   }

   make_seq(0, n, n, n);

   answer(a, pos);
}

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