Problem:
Score : 300 points

Problem Statement

1000000000000001 dogs suddenly appeared under the roof of Roger's house, all of which he decided to keep. The dogs had been numbered 1 through 1000000000000001, but he gave them new names, as follows:

the dogs numbered 1,2,\cdots,26 were respectively given the names a, b, ..., z;

the dogs numbered 27,28,29,\cdots,701,702 were respectively given the names aa, ab, ac, ..., zy, zz;

the dogs numbered 703,704,705,\cdots,18277,18278 were respectively given the names aaa, aab, aac, ..., zzy, zzz;

the dogs numbered 18279,18280,18281,\cdots,475253,475254 were respectively given the names aaaa, aaab, aaac, ..., zzzy, zzzz;

the dogs numbered 475255,475256,\cdots were respectively given the names aaaaa, aaaab, ...;

and so on.

To sum it up, the dogs numbered 1, 2, \cdots were respectively given the following names:

a, b, ..., z, aa, ab, ..., az, ba, bb, ..., bz, ..., za, zb, ..., zz, aaa, aab, ..., aaz, aba, abb, ..., abz, ..., zzz, aaaa, ...

Now, Roger asks you:

"What is the name for the dog numbered N?"

Constraints

N is an integer.

1 \leq N \leq 1000000000000001

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer to Roger's question as a string consisting of lowercase English letters.

Sample Input 1

2

Sample Output 1

b

Sample Input 2

27

Sample Output 2

aa

Sample Input 3

123456789

Sample Output 3

jjddja

Solution in C++ (GCC 9.2.1) (judge verdict: Wrong Answer)

/* 
Mohit Dhattarwal
*/
#include <bits/stdc++.h>
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
 
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define foreach(it, v) for(auto it=(v).begin(); it != (v).end(); ++it)
#define gcd(a,b) __gcd(a,b)
 
#define fastio() ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define filewr() freopen("input.txt","r",stdin);freopen("output.txt","w",stdout);
 
#define tr(...) cout<<__FUNCTION__<<' '<<__LINE__<<" = ";trace(#__VA_ARGS__, __VA_ARGS__)
 
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<string,ll> psl;
typedef pair<ll,string> pls;
 
template<typename S, typename T> 
ostream& operator<<(ostream& out,pair<S,T> const& p){out<<'('<<p.fi<<", "<<p.se<<')';return out;}
 
template<typename T>
ostream& operator<<(ostream& out,vector<T> const& v){
int l=v.size();for(int i=0;i<l-1;i++)out<<v[i]<<' ';if(l>0)out<<v[l-1];return out;}
 
template<typename T>
void trace(const char* name, T&& arg1){cout<<name<<" : "<<arg1<<endl;}
 
template<typename T, typename... Args>
void trace(const char* names, T&& arg1, Args&&... args){
const char* comma = strchr(names + 1, ',');cout.write(names, comma-names)<<" : "<<arg1<<" | ";trace(comma+1,args...);}
 
const ld PI = 3.1415926535897932384626433832795;
 
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> indexed_set;

void solve()
{
	ll n;
	cin>>n;
	string ans = "";
	while(n>0)
	{
		ll num = n%26;
		n/=26;
		if(num==0)
		{
			ans+="z";
			n--;
		}
		else
		{
			ans+=(num-1)+'a';
		}
	}
	cout<<ans<<'\n';
}

int main(){
	fastio();
	ll t;
	t=1;
	while(t--)
	{
		solve();
	}
	return 0;
}