Submission #497375

#	Time	Username	Problem	Language	Result	Execution time	Memory
497375		Ai7081	Combo (IOI18_combo)	C++17	100 / 100	28 ms	668 KiB

combo

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

int press(string p);

string guess_sequence(int n) {
    int in, t;
    string out, s, c;
    in = press("AB");
    if (in) {
        in = press("A");
        in ? out="A" : out="B";
    }
    else {
        in = press("X");
        in ? out="X" : out="Y";
    }

    string tmp = "ABXY";
    for (int i=0; i<4; i++) if (tmp[i]!=out[0]) c+=tmp[i];

    for (t=1; t<n-1; t++) {
        s = out;
        s += c[0];
        for (int i=0; i<3; i++) {
            s += out;
            s += c[1];
            s += c[i];
        }
        in = press(s);
        if (in == t) out+=c[2];
        else if (in == t+1) out+=c[0];
        else if (in == t+2) out+=c[1];
    }
    if (t==n-1) {
        if (n == press(out+c[0])) out+=c[0];
        else if (n == press(out+c[1])) out+=c[1];
        else out+=c[2];
    }
    return out;
}

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