Submission #87146

#	Time	Username	Problem	Language	Result	Execution time	Memory
87146		solimm4sks	Combo (IOI18_combo)	C++14	100 / 100	57 ms	512 KiB

combo

#include <combo.h>

std::string guess_sequence(int N)
{
    using namespace std;

    int n = N;
    string str = "";
    char first;

    {
        int x, y;
        x = press("AB");
        y = press("BX");

        if(x == 0 && y == 0){
            first = 'Y';
        }
        if(x >= 1 && y == 0){
            first = 'A';
        }
        if(x == 0 && y >= 1){
            first = 'X';
        }
        if(x >= 1 && y >= 1){
            first = 'B';
        }
    }
    str += first;

    if((int)str.size() == n){
        return str;
    }

    if(first == 'Y'){
        for(int i = 0; i < n - 1; ++i){
            int delta = str.size();
            if(delta == n - 1){
                break;
            }
            int x = press(str + "A" + str + "BA" + str + "BB" + str + "BX");

            if(x - delta == 0){
                str += "X";
            }
            if(x - delta == 1){
                str += "A";
            }
            if(x - delta == 2){
                str += "B";
            }
        }

        int delta = str.size();
        int x = press(str + "A");
        int y = press(str + "B");

        if(x - delta == 0 && y - delta == 0){
            str += "X";
        }
        if(x - delta == 1){
            str += "A";
        }
        if(y - delta == 1){
            str += "B";
        }
    }
    if(first == 'A'){
        for(int i = 0; i < n - 1; ++i){
            int delta = str.size();
            if(delta == n - 1){
                break;
            }
            int x = press(str + "Y" + str + "BY" + str + "BB" + str + "BX");

            if(x - delta == 0){
                str += "X";
            }
            if(x - delta == 1){
                str += "Y";
            }
            if(x - delta == 2){
                str += "B";
            }
        }

        int delta = str.size();
        int x = press(str + "X");
        int y = press(str + "Y");

        if(x - delta == 0 && y - delta == 0){
            str += "B";
        }
        if(x - delta == 1){
            str += "X";
        }
        if(y - delta == 1){
            str += "Y";
        }
    }
    if(first == 'X'){
        for(int i = 0; i < n - 1; ++i){
            int delta = str.size();
            if(delta == n - 1){
                break;
            }
            int x = press(str + "A" + str + "BA" + str + "BB" + str + "BY");

            if(x - delta == 0){
                str += "Y";
            }
            if(x - delta == 1){
                str += "A";
            }
            if(x - delta == 2){
                str += "B";
            }
        }

        int delta = str.size();
        int x = press(str + "A");
        int y = press(str + "B");

        if(x - delta == 0 && y - delta == 0){
            str += "Y";
        }
        if(x - delta == 1){
            str += "A";
        }
        if(y - delta == 1){
            str += "B";
        }
    }
    if(first == 'B'){
        for(int i = 0; i < n - 1; ++i){
            int delta = str.size();
            if(delta == n - 1){
                break;
            }
            int x = press(str + "A" + str + "XA" + str + "XX" + str + "XY");

            if(x - delta == 0){
                str += "Y";
            }
            if(x - delta == 1){
                str += "A";
            }
            if(x - delta == 2){
                str += "X";
            }
        }

        int delta = str.size();
        int x = press(str + "X");
        int y = press(str + "Y");

        if(x - delta == 0 && y - delta == 0){
            str += "A";
        }
        if(x - delta == 1){
            str += "X";
        }
        if(y - delta == 1){
            str += "Y";
        }
    }

    return str;
}

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