Submission #713084

#	Time	Username	Problem	Language	Result	Execution time	Memory
713084		dungnguyenn_05	Combo (IOI18_combo)	C++17	30 / 100	45 ms	548 KiB

combo

#include "combo.h"
#include<bits/stdc++.h>
#define fs first
#define sc second
#define pb push_back
#define all(x) x.begin()x.end()
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pi;

char c[5]={'A','B','X','Y'};
vi ava;
vector<pi> srt;


std::string guess_sequence(int N) {

    srand(time(0));

    int start=3;
    for(int i=0;i<3;i++)
    {
        string s;
        s+=c[i];

        int val=press(s);
        if(val)
        {
            start=i;
            break;
        }
    }

    string cur;
    cur+=c[start];

    for(int i=0;i<4;i++)
        if(i!=start)
            ava.pb(i);

    srt.pb({ava[0],ava[1]});
    srt.pb({ava[1],ava[2]});
    srt.pb({ava[0],ava[2]});

    while(cur.size()<N-1)
    {
        // cout<<"cur "<<cur<<endl;

        int pos=abs(rand()%3);

        // pos=0;

        pi k=srt[pos];

        int other;
        for(int x:ava)
            if(x!=k.fs and x!=k.sc)
                other=x;

        string ask;
        ///////////////////
        ask+=cur;
        ask+=c[k.fs];
        ask+=c[k.fs];
        ///////////////////
        ask+=cur;
        ask+=c[k.sc];
        ask+=c[k.sc];
        ///////////////////
        ask+=cur;
        ask+=c[k.fs];
        ask+=c[k.sc];
        ///////////////////
        ask+=cur;
        ask+=c[k.sc];
        ask+=c[k.fs];
        ///////////////////


        int val=press(ask)-cur.size();

        // cout<<ask<<' '<<val<<endl;

        if(!val)
        {
            cur+=c[other];
            continue;
        }

        if(val==1)
        {
            string nw;
            nw=cur+c[k.fs];

            if(press(nw)-cur.size())
                cur+=c[k.fs];
            else
                cur+=c[k.sc];

            cur+=c[other];

            continue;
        }

        if(val==2)
        {
            ask="";
            ///////////////////
            ask+=cur;
            ask+=c[k.fs];
            ask+=c[k.fs];
            ///////////////////
            ask+=cur;
            ask+=c[k.sc];
            ask+=c[k.sc];
            ///////////////////

            if(press(ask)-cur.size()>=2)
            {
                ask="";
                ///////////////////
                ask+=cur;
                ask+=c[k.fs];
                ask+=c[k.fs];
                ///////////////////

                if(press(ask)-cur.size()>=2)
                {
                    cur+=c[k.fs];
                    cur+=c[k.fs];
                }
                else
                {
                    cur+=c[k.sc];
                    cur+=c[k.sc];
                }

            }
            else
            {
                ask="";
                ///////////////////
                ask+=cur;
                ask+=c[k.fs];
                ask+=c[k.sc];
                ///////////////////

                if(press(ask)-cur.size()>=2)
                {
                    cur+=c[k.fs];
                    cur+=c[k.sc];
                }
                else
                {
                    cur+=c[k.sc];
                    cur+=c[k.fs];
                }

            }
        }
    }

    if(cur.size()<N)
    {
        string ask;
        ask=cur+c[ava[0]];
        if(press(ask)-cur.size()>0)
            cur+=c[ava[0]];

        ask=cur+c[ava[1]];
        if(press(ask)-cur.size()>0)
            cur+=c[ava[1]];
    }

    if(cur.size()<N)
        cur+=c[ava[2]];

    // cout<<cur<<endl;


    return cur;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:45:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   45 |     while(cur.size()<N-1)
      |           ~~~~~~~~~~^~~~
combo.cpp:163:18: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  163 |     if(cur.size()<N)
      |        ~~~~~~~~~~^~
combo.cpp:175:18: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  175 |     if(cur.size()<N)
      |        ~~~~~~~~~~^~
combo.cpp:86:25: warning: 'other' may be used uninitialized in this function [-Wmaybe-uninitialized]
   86 |             cur+=c[other];
      |                  ~~~~~~~^

• Subtask 1: 5 / 5
• Subtask 2: 25 / 95