#include<iostream>
using namespace std;
void f(int n,char A,char B, char C) {
	
	if(n==1) {
		cout<<A<<" To "<<C<<endl;
		return;
	}
	f(n-1,A,C,B);
	cout<<A<<" To "<<C<<endl;
	f(n-1,B,A,C);
}
int main() {
	int n;
	cin>>n;
	f(n,'A','B','C');
} 

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