Submission #1338910

#	Time	Username	Problem	Language	Result	Execution time	Memory
1338910		luvwinter	Combo (IOI18_combo)	C++20	Compilation error	0 ms	0 KiB

combo

#include<bits/stdc++.h>
#include "combo.h"

#define boost() ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
#define dd long double
#define pii pair<int , int>
#define pb push_back
#define pf push_front
#define ppf pop_front
#define ppb pop_back
#define in insert
#define lb lower_bound
#define ub upper_bound
#define FOR(i , l , r) for(int i = (l) ; i <= (r) ; i ++)
#define FOD(i , r , l) for(int i = (r) ; i >= (l) ; i --)
#define endl '\n'
#define all(x) x.begin() , x.end()
#define sz(a) (int)a.size()
#define fi first
#define se second
#define mp make_pair

using namespace std;

const string NAME = "";
vector<char> ss = {'X' , 'Y' , 'A' , 'B'};


string guess_sequence(int n) {
    string s = "AB";
    if(press(s) == 0){
        if(press("X") == 0) s = "Y";
        else s = "X";
    }
    else {
        if(press("A") == 0) s = "B";
        else s = "A";
    }
    if(n == 1) return s;
    vector<char> c;
    for(auto x : ss) {
        if(x == s[0]) continue;
        else c.pb(x);
    }

    FOR(i , 1 , n - 1) {
        string tmp = res + c[0];
        for(auto x : c) {
            tmp += res + c[1] + x;
        }
        int k = press(tmp);
        if(sz(res) == k - 1) {
            res += c[0];
        }
        else if(sz(res) == k - 2) {
            res += c[1];
        }
        else{
            res += c[2];
        }

    }

    return res;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:48:22: error: 'res' was not declared in this scope
   48 |         string tmp = res + c[0];
      |                      ^~~
combo.cpp:65:12: error: 'res' was not declared in this scope
   65 |     return res;
      |            ^~~