#include<bits/stdc++.h>
using namespace std;
string s="0ABCDEFGHIJKLMNOPQRSTUVWXYZ";
int main(){
	int n;
	cin>>n;
	if (n%26==0){
		for (int i=1;i<=100;++i){
			char j=i;
			if (j>='A' && j<='Z') cout<<j;
		}
		return 0;
	}
	for (int i=n+1;i<=26;++i) cout<<s[i];
	for (int i=1;i<=n;++i) cout<<s[i];
	return 0;
}