#include<iostream>#include<string>#include<cstdio>#include<cstring>using namespace std;void PRintA(int n){	char ch='A';	if(n==1)		cout<<ch;	else	{		printA(n-1);		printf("%c",ch+n-1);		printA(n-1);	}}int main(){	int i,n;	cin>>n;	printA(n);	return 0;}