Submission #940677

#	Time	Username	Problem	Language	Result	Execution time	Memory
940677		Macker	Combo (IOI18_combo)	C++17	100 / 100	14 ms	2000 KiB

combo

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

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
#define fi first
#define se second
#define all(v) v.begin(), v.end()
#define FOR(i, n) for (int i = 0; i < n; i++)


string guess_sequence(int N) {
    string s = "";
    char fir;
    if(press("AB")){
        if(press("A")) fir = 'A';
        else fir = 'B';
    }
    else{
        if(press("X")) fir = 'X';
        else fir = 'Y';
    }
    s.push_back(fir);
    if(N == 1) return s;

    string t("ABXY");
    int x = t.find(fir);
    t.erase(x, 1);
    FOR(i, N - 2){
        string q;
        q.append(s);
        q.append({t[0], t[0]});
        q.append(s);
        q.append({t[0], t[1]});
        q.append(s);
        q.append({t[0], t[2]});
        q.append(s);
        q.append({t[1]});
        int a = press(q) - s.size();
        if(a == 2) s.push_back(t[0]);
        else if(a == 1) s.push_back(t[1]);
        else s.push_back(t[2]);
    }

    s.push_back(t[0]);
    if(press(s) != s.size()){
        s.pop_back();
        s.push_back(t[1]);
        if(press(s) != s.size()){
            s.pop_back();
            s.push_back(t[2]);
        }
    }
    return s;
}

Compilation message (stderr)

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:49:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   49 |     if(press(s) != s.size()){
      |        ~~~~~~~~~^~~~~~~~~~~
combo.cpp:52:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |         if(press(s) != s.size()){
      |            ~~~~~~~~~^~~~~~~~~~~

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