Submission #1011166

#	Time	Username	Problem	Language	Result	Execution time	Memory
1011166		AlgorithmWarrior	Combo (IOI18_combo)	C++14	Compilation error	0 ms	0 KiB

combo

string guess_sequence(int N)
{
    string ans="";
    char ch1,ch2,ch3,ch4;
    if(press("AB"))
    {
        if(press("A"))
        {
            ch1='A';
            ch2='B';
            ch3='X';
            ch4='Y';
        }
        else
        {
            ch1='B';
            ch2='A';
            ch3='X';
            ch4='Y';
        }
    }
    else
    {
        if(press("X"))
        {
            ch1='X';
            ch2='A';
            ch3='B';
            ch4='Y';
        }
        else
        {
            ch1='Y';
            ch2='A';
            ch3='B';
            ch4='X';
        }
    }
    ans+=ch1;
    int i;
    for(i=2;i<N;++i)
    {
        int val=press(ans+ch3+ans+ch4+ch2+ans+ch4+ch3+ans+ch4+ch4);
        if(val==i-1)
            ans+=ch2;
        if(val==i)
            ans+=ch3;
        if(val==i+1)
            ans+=ch4;
    }
    if(press(ans+ch2)==N) return ans+ch2;
    if(press(ans+ch3)==N) return ans+ch3;
    return ans+ch4;
}

Compilation message (stderr)

combo.cpp:1:1: error: 'string' does not name a type
    1 | string guess_sequence(int N)
      | ^~~~~~