Submission #133180

#	Time	Username	Problem	Language	Result	Execution time	Memory
133180		nxteru	Combo (IOI18_combo)	C++14	100 / 100	67 ms	536 KiB

combo

#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string ans;
char c[3],d[4]={'A','B','X','Y'};
bool u[4];
string q;
string guess_sequence(int n){
  q+=d[0];
  q+=d[1];
  if(press(q)>=1){
    q.pop_back();
    if(press(q)>=1)u[0]=true;
    else u[1]=true;
  }else{
    q.clear();
    q.push_back(d[2]);
    if(press(q)>=1)u[2]=true;
    else u[3]=true;
  }
  int k=0;
  for(int i=0;i<4;i++){
    if(!u[i])c[k++]=d[i];
    else ans.push_back(d[i]);
  }
  for(int i=2;i+1<=n;i++){
    q.clear();
    q+=ans;
    q.push_back(c[0]);
    for(int j=0;j<3;j++){
      q+=ans;
      q.push_back(c[1]);
      q.push_back(c[j]);
    }
    int s=press(q);
    if(s==i-1)ans.push_back(c[2]);
    else if(s==i)ans.push_back(c[0]);
    else ans.push_back(c[1]);
  }
  if(ans.size()==n){
    ans.push_back('\0');
    return ans;
  }
  q.clear();
  q+=ans;
  q.push_back(c[0]);
  q+=ans;
  q.push_back(c[1]);
  if(press(q)==n){
    q.clear();
    q+=ans;
    q.push_back(c[0]);
    if(press(q)==n)ans.push_back(c[0]);
    else ans.push_back(c[1]);
  }else ans.push_back(c[2]);
  ans.push_back('\0');
  return ans;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:41:16: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   41 |   if(ans.size()==n){
      |      ~~~~~~~~~~^~~

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