Submission #714709

#	Time	Username	Problem	Language	Result	Execution time	Memory
714709		bin9638	Combo (IOI18_combo)	C++17	100 / 100	38 ms	660 KiB

combo

#include<bits/stdc++.h>

#ifndef SKY
#include "combo.h"
#endif // SKY

using namespace std;
#define N 510
#define ll long long
#define ii pair<int,int>
#define fs first
#define sc second
#define pb push_back
#define iii pair<int,ii>

#ifdef SKY
string s;
int press(string p)
{
    //cout<<s<<" "<<p<<endl;
    for(int sz=s.size();sz>=1;sz--)
    {
        for(int i=0;i+sz-1<p.size();i++)
            if(s.substr(0,sz)==p.substr(i,sz))
                return sz;
    }
    return 0;
}
#endif

vector<char>kt;

string guess_sequence(int n)
{
    char start;
    if(press("XY")==0)
    {
        if(press("A")==0)
            start='B';
                else start='A';
    }else
    {
        if(press("X")==0)
            start='Y';
                else start='X';
    }
    vector<char>cc={'A','B','X','Y'};
    for(auto ch:cc)
        if(ch!=start)
            kt.pb(ch);
    string kq="";
    kq.pb(start);
    for(int i=1;i<n-1;i++)
    {
        string ask="";
        ask+=kq+kt[0];
        ask+=kq+kt[1]+kt[0]+kq+kt[1]+kt[1]+kq+kt[1]+kt[2];
        int val=press(ask);
        if(val==kq.size())
        {
            kq.pb(kt[2]);
            continue;
        }
        if(val==kq.size()+1)
        {
            kq.pb(kt[0]);
            continue;
        }
        if(val==kq.size()+2)
        {
            kq.pb(kt[1]);
            continue;
        }
    }
    if(n==1)
        return kq;
    if(press(kq+kt[0]+kq+kt[1])==kq.size()+1)
    {
        if(press(kq+kt[0])==kq.size()+1)
            kq.pb(kt[0]);
                else kq.pb(kt[1]);
    }else
        kq.pb(kt[2]);
    return kq;
}

#ifdef SKY
int main()
{
    freopen("A.inp","r",stdin);
    freopen("A.out","w",stdout);
    ios::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    cin>>s;
    cout<<(s==guess_sequence(s.size()));
    return 0;
}
#endif // SKY

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:59:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |         if(val==kq.size())
      |            ~~~^~~~~~~~~~~
combo.cpp:64:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |         if(val==kq.size()+1)
      |            ~~~^~~~~~~~~~~~~
combo.cpp:69:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   69 |         if(val==kq.size()+2)
      |            ~~~^~~~~~~~~~~~~
combo.cpp:77:32: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |     if(press(kq+kt[0]+kq+kt[1])==kq.size()+1)
      |        ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~
combo.cpp:79:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |         if(press(kq+kt[0])==kq.size()+1)
      |            ~~~~~~~~~~~~~~~^~~~~~~~~~~~~

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