Submission #75118

#	Time	Username	Problem	Language	Result	Execution time	Memory
75118		imeimi2000	Combo (IOI18_combo)	C++17	100 / 100	52 ms	612 KiB

combo

#include "combo.h"
using namespace std;

string guess_sequence(int n) {
    char cs[] = "ABXY";
    if (press("AB")) {
        if (press("A")) swap(cs[3], cs[0]);
        else swap(cs[3], cs[1]);
    }
    else if (press("X")) swap(cs[3], cs[2]);
    string ret = ""; ret += cs[3];
    if (n == 1) return ret;
    for (int i = 1; i < n - 1; ++i) {
        string Q = "";
        Q += ret; Q += cs[1];
        Q += ret; Q += cs[2]; Q += cs[0];
        Q += ret; Q += cs[2]; Q += cs[1];
        Q += ret; Q += cs[2]; Q += cs[2];
        int R = press(Q);
        ret += cs[R - i];
    }
    if (press(ret + cs[0]) == n) return ret + cs[0];
    if (press(ret + cs[1]) == n) return ret + cs[1];
    return ret + cs[2];
}

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