Submission #1100194

#	Time	Username	Problem	Language	Result	Execution time	Memory
1100194		radaiosm7	Cave (IOI13_cave)	C++98	100 / 100	187 ms	760 KiB

cave

#include "cave.h"
#include <bits/stdc++.h>
using namespace std;
int corrPos, corrState, l, r;
bool done[5005];
vector<int> switches;

void exploreCave(int N) {
  for (int i=0; i < N; ++i) done[i] = false;
  int S[N], D[N];

  for (int i=0; i < N; ++i) {
    switches.clear();
    for (int j=0; j < N; ++j) if (!done[j]) switches.push_back(j);
    for (int j=0; j < N-i; ++j) S[switches[j]] = 0;
    corrState = (tryCombination(S) == i) ? 1 : 0;
    for (int j=0; j < N-i; ++j) S[switches[j]] = corrState^1;

    l = 0;
    r = N-i-1;
    corrPos = -1;

    while (l <= r) {
      int mid = (l+r)/2;
      for (int j=l; j <= mid; ++j) S[switches[j]] = corrState;
      int firstOpen = tryCombination(S);
      for (int j=l; j <= mid; ++j) S[switches[j]] = corrState^1;

      if (firstOpen == i) l = mid+1;

      else {
        corrPos = switches[mid];
        r = mid-1;
      }
    }

    done[corrPos] = true;
    S[corrPos] = corrState;
    D[corrPos] = i;
  }

  answer(S, D);
}

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