Submission #162752

#	Time	Username	Problem	Language	Result	Execution time	Memory
162752		Minnakhmetov	Combo (IOI18_combo)	C++14	100 / 100	60 ms	464 KiB

combo

#include <bits/stdc++.h>
#include "combo.h"
using namespace std;

#define all(aaa) aaa.begin(), aaa.end()

void guess_one_letter(string &s, string t) {
    int l = -1, r = t.size() - 1;
    while (r - l > 1) {
        int p = (l + r) >> 1;
        string g;

        for (int i = 0; i <= p; i++) {
            g += s + string(1, t[i]);
        }

        if (press(g) >= s.size() + 1)
            r = p;
        else
            l = p;
    }
    s.push_back(t[r]);
}

string guess_sequence(int n) {
    string s, t = "AXYB";

    guess_one_letter(s, t);

    t.erase(find(all(t), s[0]));

    for (int i = 2; i < n; i++) {
        string p = s + string(1, t[0])
            + s + string(1, t[1]) + string(1, t[0])
            + s + string(1, t[1]) + string(1, t[1])
            + s + string(1, t[1]) + string(1, t[2]);

        int coins = press(p);
        if (coins == i)
            s.push_back(t[0]);
        else if (coins == i + 1)
            s.push_back(t[1]);
        else
            s.push_back(t[2]);
    }

    if (n > 1)
        guess_one_letter(s, t);

    return s;  
}

Compilation message (stderr)

combo.cpp: In function 'void guess_one_letter(std::string&, std::string)':
combo.cpp:17:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   17 |         if (press(g) >= s.size() + 1)
      |             ~~~~~~~~~^~~~~~~~~~~~~~~

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