Submission #470614

#	Time	Username	Problem	Language	Result	Execution time	Memory
470614		someone	Combo (IOI18_combo)	C++14	100 / 100	40 ms	616 KiB

combo

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

const int N = 2e3 + 42;

char c[N], let[4];

std::string guess_sequence(int n) {
    for(int i = 0; i < n; i++)
        c[i] = '#';
    int l = press("AB");
    if(l == 0) {
        l = press("X");
        if(l == 0)
            c[0] = 'Y';
        else
            c[0] = 'X';
    } else if(l == 1) {
        l = press("A");
        if(l == 0)
            c[0] = 'B';
        else
            c[0] = 'A';
    } else {
        c[0] = 'A';
        c[1] = 'B';
    }
    let[0] = 'A';
    let[1] = 'B';
    let[2] = 'X';
    let[3] = 'Y';
    for(int i = 0; i < 4; i++)
        if(let[i] == c[0])
            let[i] = 'Z';
    sort(let, let + 4);
    string tot = "";
    tot += c[0];
    for(int i = 1; i < n-1; i++) {
        if(c[i] == '#') {
            l = press(tot + let[0] + tot + let[1] + let[0] + tot + let[1] + let[1] + tot + let[1] + let[2]);
            if(l == i)
                c[i] = let[2];
            else if(l == i+1)
                c[i] = let[0];
            else
                c[i] = let[1];
        }
        tot += c[i];
    }
    if(n != 1) {
        l = press(tot + let[0] + tot + let[1]);
        if(l == n) {
            l = press(tot + let[0]);
            if(l == n)
                c[n-1] = let[0];
            else
                c[n-1] = let[1];
        } else {
            c[n-1] = let[2];
        }
        tot += c[n-1];
    }
    return tot;
}

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