#include<cstdio>
#include<cmath>
#include<cctype>
#include<iostream>
#include<vector>
#include<cstring>
#include<algorithm>
#include<map>
#include<set>
#include<cstddef>
#include<sstream>
#include<cstdlib>
#include<stack>
#include<queue>
using namespace std;
void f(int n,char a,char b,char c)
{
if(n==1) printf("1 from %c to %c
",a,c);///分解的最小问题一定是1怎么移动
else
{
f(n-1,a,c,b);
printf("%d from %c to %c
",n,a,c);///分解步骤:最简单的访问就是输出
f(n-1,b,a,c);
}
}
int main()
{
int siz=0;
int n;
cin>>n;
for(int i=1;i<=n;++i)
{
siz*=2;
siz++;
}
cout<<siz<<endl;
f(n,'A','B','C');
return 0;
}