Submission #1007211

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007211		devariaota	Combo (IOI18_combo)	C++17	100 / 100	20 ms	2068 KiB

combo

#include "combo.h"
using namespace std;
string guess_sequence(int N) {
    string ans = "";
    int val = press("AB");
    if(val >= 1){
        val = press("A");
        if(val == 1){
            ans += "A";
        }else{
            ans += "B";
        }
    }else{
        val = press("X");
        if(val >= 1){
            ans += "X";
        }else{
            ans += "Y";
        }
    }
    N--;
    if(!N){
        return ans;
    }
    if(ans == "A"){
        int old = ans.length();
        while(N-1){
            val = press(ans+"BB"+ans+"BX"+ans+"BY"+ans+"X");
            if((val-old) == 2){
                ans += "B";
            }else if((val-old)){
                ans += "X";
            }else{
                ans += "Y";
            }
            old++;
            N--;
        }
        val = press(ans+"B");
        if(val == old+1){
            ans += "B";
        }else{
            val = press(ans+"X");
            if(val == old+1){
                ans += "X";
            }else{
                ans += "Y";
            }
        }
    }else if(ans == "B"){
        int old = ans.length();
        while(N-1){
            val = press(ans+"AA"+ans+"AX"+ans+"AY"+ans+"X");
            if((val-old) == 2){
                ans += "A";
            }else if((val-old)){
                ans += "X";
            }else{
                ans += "Y";
            }
            old++;N--;
        }
        val = press(ans+"A");
        if(val == old+1){
            ans += "A";
        }else{
            val = press(ans+"X");
            if(val == old+1){
                ans += "X";
            }else{
                ans += "Y";
            }
        }
    }else if(ans == "X"){
        int old = ans.length();
        while(N-1){
            val = press(ans+"AA"+ans+"AB"+ans+"AY"+ans+"B");
            if((val-old) == 2){
                ans += "A";
            }else if((val-old)){
                ans += "B";
            }else{
                ans += "Y";
            }
            old++;N--;
        }
        val = press(ans+"B");
        if(val == old+1){
            ans += "B";
        }else{
            val = press(ans+"A");
            if(val == old+1){
                ans += "A";
            }else{
                ans += "Y";
            }
        }
    }else{
        int old = ans.length();
        while(N-1){
            val = press(ans+"AA"+ans+"AB"+ans+"AX"+ans+"B");
            if((val-old) == 2){
                ans += "A";
            }else if((val-old)){
                ans += "B";
            }else{
                ans += "X";
            }
            old++;N--;
        }
        val = press(ans+"B");
        if(val == old+1){
            ans += "B";
        }else{
            val = press(ans+"X");
            if(val == old+1){
                ans += "X";
            }else{
                ans += "A";
            }
        }
    }
    return ans;
}

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