Submission #340265

#	Time	Username	Problem	Language	Result	Execution time	Memory
340265		amano_hina	Combo (IOI18_combo)	C++14	100 / 100	42 ms	524 KiB

combo

#include "combo.h"

std::string guess_sequence(int N) {
  std::string p = "";
  std::string p2= "";
  std::string ans= "";
  int ban;
  char c[4];
  c[0]='A';
  c[1]='B';
  c[2]='X';
  c[3]='Y';
  p += c[0];
  p += c[1];
  int coins = press(p);
  if(coins>=1)
  {
      p.clear();
      p+=c[0];
      coins = press(p);
      if(coins==1)
      {
          ans+=c[0];
          ban=0;
      }
      else
      {
          ans+=c[1];
          ban=1;
      }
  }
  else
  {
      p.clear();
      p+=c[2];
      coins = press(p);
      if(coins==1)
      {
          ans+=c[2];
          ban=2;
      }
      else
      {
          ans+=c[3];
          ban=3;
      }
  }
  // 2 steps
  int pos;
  int pos2;
  int pos3;
  pos=0;
  if(pos==ban)
  {
      pos++;
  }
  pos2=pos+1;
  if(pos2==ban)
  {
      pos2++;
  }
  pos3=pos2+1;
  if(pos3==ban)
  {
      pos3++;
  }
  for(int i=1;i<N-1;i++)
  {
      p2.clear();
      for(int j=0;j<4;j++)
      {
          if(j!=ban)
          {
              p2+=ans;
              p2+=c[pos];
              p2+=c[j];
          }
      }
      p2+=ans;
      p2+=c[pos2];
      coins = press(p2);
      if(coins==i)
      {
          ans+=c[pos3];
      }
      else if(coins==i+1)
      {
          ans+=c[pos2];
      }
      else
      {
          ans+=c[pos];
      }
  }
  // n-2 steps
  if(N==1)
  {
      return ans;
  }
  else
  {
      p2.clear();
      p2+=ans;
      p2+=c[pos];
      coins = press(p2);
      if(coins==N)
      {
          std::string S = "";
          S+=ans;
          S+=c[pos];
          return S;
      }
      p2.clear();
      p2+=ans;
      p2+=c[pos2];
      coins = press(p2);
      if(coins==N)
      {
          std::string S = "";
          S+=ans;
          S+=c[pos2];
          return S;
      }
      std::string S = "";
      S+=ans;
      S+=c[pos3];
      return S;
  }

}

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