Submission #321045

#	Time	Username	Problem	Language	Result	Execution time	Memory
321045		gustason	Combo (IOI18_combo)	C++14	100 / 100	42 ms	676 KiB

combo

#include<bits/stdc++.h>
#include "combo.h"
 
using namespace std;
 
string guess_sequence(int N) {
    string S = "", q;
    int x;
 
    if (press("AB") >= 1) {
        if (press("A") == 1) {
            S += 'A';
        } else {
            S += 'B';
        }
    } else {
        if (press("X") == 1) {
            S += 'X';
        } else {
            S += 'Y';
        }
    }
 
   	if (N == 1)
        return S;
    int sz = 1;
    for(int i = 1; i < N-1; i++, sz++) {
        if (S[0] == 'A') {
            q = S + "B" + S + "XB" + S + "XX" + S + "XY";
            x = press(q);
            if (x == sz) {
                S += "Y";
            } else if (x == sz + 1) {
                S += "B";
            } else {
                S += "X";
            }
        } else if (S[0] == 'B') {
            q = S + "A" + S + "XA" + S + "XX" + S + "XY";
            x = press(q);
            if (x == sz) {
                S += "Y";
            } else if (x == sz + 1) {
                S += "A";
            } else {
                S += "X";
            }
        } else if (S[0] == 'X') {
            q = S + "A" + S + "BA" + S + "BB" + S + "BY";
            x = press(q);
            if (x == sz) {
                S += "Y";
            } else if (x == sz + 1) {
                S += "A";
            } else {
                S += "B";
            }
        } else {
            q = S + "A" + S + "XA" + S + "XB" + S + "XX";
            x = press(q);
            if (x == sz) {
                S += "B";
            } else if (x == sz + 1) {
                S += "A";
            } else {
                S += "X";
            }
        }
    }
 
    if (S[0] != 'A') {
        q = S + "A";
        x = press(q);
        if (x == N) return q;
    }
    if (S[0] != 'B') {
        q = S + "B";
        x = press(q);
        if (x == N) return q;
    }
    if (S[0] != 'X') {
        if (S[0] == 'Y') {
            S += 'X';
            return S;
        }
        q = S + "X";
        x = press(q);
        if (x == N) return q;
    }
    S += "Y";
    return S;
}

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