Submission #553652

#	Time	Username	Problem	Language	Result	Execution time	Memory
553652		MadokaMagicaFan	Combo (IOI18_combo)	C++14	Compilation error	0 ms	0 KiB

combo

#include<bits/stdc++.h>
int fc;

char ps[4] = {'A','B','X','Y'};

char getc(int x){
    if (x >= fc)
        ++x;
    return ps[x];
}

string guess_sequence(int N){
    string s = "";

    // char 1
    if (press("AB")){
        if (press("A"))
            fc = 0;
        else
            fc = 1;
    } else {
        if (press("X"))
            fc = 2;
        else
            fc = 3;
    }

    s += ps[fc];

    if (N==1)
        return s;

    --N;

    while(--N){
        string q = s + getc(0) + 
            s + getc(1) + getc(0) +
            s + getc(1) + getc(1) +
            s + getc(1) + getc(2);

        int ans = press(q);

        if(ans == s.size())
            s += getc(2);
        else if(ans == s.size() + 1)
            s += getc(0);
        else
            s += getc(1);
    }

    if (press(s+getc(0)) == s.size() + 1)
        s += getc(0);
    else if (press(s+getc(1)) == s.size() + 1)
        s += getc(1);
    else
        s += getc(2);

    return s;
}

Compilation message (stderr)

combo.cpp:12:1: error: 'string' does not name a type; did you mean 'stdin'?
   12 | string guess_sequence(int N){
      | ^~~~~~
      | stdin