#define _CRT_SECURE_NO_WARNINGS

#include<iostream>

#include<vector>

#include<cstring>

#include<set>

#include<algorithm>

#include<stack>

#include<string>

#include<cstdio>

#define _for(i, a, b) for (int i = (a); i<(b); ++i)

using namespace std;

struct problem {

    int n;

    char scr, mid, dest;

    problem(int nn, char s, char m, char d) :n(nn), scr(s), mid(m), dest(d) {}

};

stack<problem> stk;

int main()

{

    int n;

    cin >> n;

    stk.push(problem(n, 'A', 'B', 'C'));

        while (!stk.empty()) {

            problem now = stk.top();

            stk.pop();

            if (now.n == ) { cout << now.scr << "->" << now.dest << endl; }

            else {

                stk.push(problem(now.n - , now.mid, now.scr, now.dest));//先放最后一个子问题

                stk.push(problem(, now.scr, now.mid, now.dest));

                stk.push(problem(now.n - , now.scr, now.dest, now.mid));

            }

        }

    system("pause");

}