Submission #160285

#	Time	Username	Problem	Language	Result	Execution time	Memory
160285		DavidDamian	Combo (IOI18_combo)	C++11	100 / 100	50 ms	584 KiB

combo

#include<iostream>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <string>
#include "combo.h"
using namespace std;

string guess_sequence(int N) ///Guess the combo sequence
{
    string p="";
    string Q="AB";
    char letter[4];
    char l[4]={'A','B','X','Y'};
    int answer=press(Q);
    if(answer>=1){ //We find the first letter in two queries
        if(press("A"))
            p+='A';
        else
            p+='B';
    }
    else{
        if(press("X"))
            p+='X';
        else
            p+='Y';
    }
    int j=0;
    for(int i=0;i<4;i++){ //Ans we eliminate it from possible letters
        if(p[0]!=l[i]){
            letter[j++]=l[i];
        }
    }
    for(int i=2;i<N;i++){ //For each letter we guess it making a query with 3 different return values (one for each letter)
        Q=p+letter[0]+p+letter[1]+letter[0]+p+letter[1]+letter[1]+p+letter[1]+letter[2];
        answer=press(Q);
        if(answer==i-1){
            p+=letter[2];
        }
        else if(answer==i){
            p+=letter[0];
        }
        else if(answer==i+1){
            p+=letter[1];
        }
    }
    if(N>1){ //We guess the last letter with two queries
        if(press(p+letter[0])==N){
            p+=letter[0];
        }
        else if(press(p+letter[1])==N){
            p+=letter[1];
        }
        else{
            p+=letter[2];
        }
    }
    return p;
}

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