Submission #154072

#	Time	Username	Problem	Language	Result	Execution time	Memory
154072		nthoang	Combo (IOI18_combo)	C++11	97 / 100	54 ms	576 KiB

combo

#include <bits/stdc++.h>

#ifndef LOCAL
#include "combo.h"
#endif

#ifdef LOCAL
#include "/Users/nth842002/Library/debug.h"
int press(string p) { }
int main() { }
#endif

using namespace std;

const string moves = "ABXY";

string guess_sequence(int n) {
  string s;
  for (int i = 0; i < 3; i++) {
    s += moves[i];
    if (press(s) == 1) {
      break;
    }
    s.pop_back();
  }
  if (s.empty()) {
    s += moves[3];
  }
  string avail;
  for (int i = 0; i < 4; i++) {
    if (moves[i] != s[0]) {
      avail += moves[i];
    }
  }
  for (int i = 1; i < n - 1; i++) {
    string t = s + avail[0];
    t += s + avail[1] + avail[0];
    t += s + avail[1] + avail[1];
    t += s + avail[1] + avail[2];
    int c = press(t);
    if (c == (int) s.length() + 1) {
      s += avail[0];
    } else if (c == (int) s.length() + 2) {
      s += avail[1];
    } else {
      s += avail[2];
    }
  }
  if (n > 1) {
    for (int i = 0; i < 2; i++) {
      s += avail[i];
      if (press(s) == n) {
        break;
      }
      s.pop_back();
    }
    if ((int) s.length() < n) {
      s += avail[2];
    }  
  }
  return s;
}

/* Subtask: q <= 2N + 1

string guess_sequence(int n) {
  srand(time(0));
  string s;
  for (int i = 0; i < 3; i++) {
    string t;
    t += moves[i];
    if (press(t) == 1) {
      s += moves[i];
      break;
    }
  }
  if (s.empty()) {
    s += moves[3];
  }
  string avail;
  for (int i = 0; i < 4; i++) {
    if (moves[i] != s[0]) {
      avail += moves[i];
    }
  }
  for (int i = 1; i < n; i++) {
    random_shuffle(avail.begin(), avail.end());
    for (int j = 0; j < 2; j++) {
      s += avail[j];
      if (press(s) == i + 1) {
        break;
      }
      s.pop_back();
    }
    if (s.length() == i) {
      s += avail[2];
    }
  }
  assert((int) s.length() == n);
  return s;
}

*/

• Subtask 1: 5 / 5
• Subtask 2: 92 / 95